UGREEN 70158 Bluetooth 5.0 Optical/AUX Transmitter/Receiver
Overview
UGREEN 70158 is a rechargeable Bluetooth 5.0 transmitter/receiver with optical digital and 3.5mm analogue audio paths for televisions, headphones and home audio. Below: direction, pairing, codec limits, microphone behaviour, battery expectations and safe use without borrowing claims from similar UGREEN products.
- OPTICAL + 3.5MM • TX/RX • APTX FAMILY
- SKU 70158
- Bluetooth 5.0 Optical/AUX Adapter
- Black
- TX + RX
What it does well.
Key features
What it does. a rechargeable Bluetooth 5.0 transmitter/receiver with optical digital and 3.5mm analogue audio paths for televisions, headphones and home audio.
Audio direction. TX sends sound from a TV/player’s optical output or 3.5mm output to Bluetooth headphones/speakers. RX receives phone/tablet Bluetooth audio and outputs it through optical or 3.5mm to an amplifier, powered speaker or receiver.
Codec boundary. The listing and media identify aptX, aptX HD and aptX Low Latency support. The active codec still depends on the paired endpoint; SBC fallback should be expected when the other device lacks aptX. LDAC is not claimed.
Compatibility boundary. Optical S/PDIF or 3.5mm sources in TX; optical or 3.5mm destinations in RX; Bluetooth headphones, speakers, phones and tablets with a common supported codec.
Audio direction: source → product → listener
TX sends sound from a TV/player’s optical output or 3.5mm output to Bluetooth headphones/speakers. RX receives phone/tablet Bluetooth audio and outputs it through optical or 3.5mm to an amplifier, powered speaker or receiver.
Why direction matters: transmitter, receiver and headset roles are not interchangeable. A Bluetooth version number also does not establish microphone return, codec, multipoint or low latency.
Before pairing: identify the wired input/output, set the correct operating mode and lower volume at every powered endpoint.
Sound, codecs and latency
Codec support. The listing and media identify aptX, aptX HD and aptX Low Latency support. The active codec still depends on the paired endpoint; SBC fallback should be expected when the other device lacks aptX. LDAC is not claimed.
Delay and sync. aptX Low Latency requires compatible support at both ends. “No lag” is not repeated as a guarantee; TV processing, optical settings and headphone codec selection can still affect sync.
Real-world sound. Final fidelity depends on the source file, negotiated codec, RF conditions, transducers, fit, amplifier and volume. “Bluetooth 5.x” alone is not a sound-quality tier.
For games and video. Treat every millisecond figure as a controlled test result. Wireless display processing, game engines and headset buffering can add delay.
Use scenarios
Scenario 1. TV optical output to Bluetooth headphones.
Scenario 2. TV 3.5mm output to two Bluetooth listeners.
Scenario 3. Phone music to a home amplifier through optical or AUX.
Scenario 4. Legacy CD/MP3 player to Bluetooth speakers.
Scenario 5. Long sessions powered from a suitable USB source after noise testing.
Setup and usability guidance
Best practice: pair one endpoint first, verify stable audio, then add any supported second endpoint. This makes faults easier to isolate.
Controls. Physical switches select TX/RX and optical/AUX path; pairing controls manage device links. Set the TV to a supported stereo PCM output when optical audio is silent.
Microphone and calls. No microphone or call profile is for SKU 70158. Treat it as programme-audio equipment, not a hands-free car kit or headset-microphone bridge.
Two-device behaviour. Dual link supports two devices in TX and is listed for RX. It does not mix sources or create independent volume and codec behaviour can change when two listeners are connected.
Reset path. Clear pairings through the model’s documented control sequence and remove old Bluetooth records from the endpoints. Power-cycle after changing TX/RX or optical/AUX modes.
- Step 1: Charge the unit and choose TX or RX while powered off.
- Step 2: Choose optical or AUX, then connect to the correct source output (TX) or destination input (RX).
- Step 3: For optical TV use, select PCM/stereo output; Dolby/DTS bitstreams are not claimed for Bluetooth conversion.
- Step 4: Enter pairing mode and pair the first Bluetooth endpoint.
- Step 5: Use the documented dual-link sequence for a second endpoint and confirm both actually reproduce audio.
Compatible devices and systems
Compatibility class: Optical S/PDIF or 3.5mm sources in TX; optical or 3.5mm destinations in RX; Bluetooth headphones, speakers, phones and tablets with a common supported codec.
- Match Bluetooth audio capability, not just the word Bluetooth. Some TVs, consoles and computers support controllers or data but not Bluetooth audio.
- Confirm whether the desired direction is sending audio, receiving audio or returning a microphone. These are separate capabilities.
- Confirm physical connector role and audio type: analogue AUX, optical PCM or USB audio are not interchangeable.
- Update the host operating system and test with other saved Bluetooth devices temporarily disconnected.
- When using branded earbuds/headphones, check their pairing limits and supported codec list too.
What this product does
- Switches between Bluetooth transmitter and receiver roles.
- Uses the documented wired audio interface as input in TX and output in RX.
- Supports the dual-pair and call behaviour stated above.
- Runs from its rechargeable battery for portable use.
- Reconnects to saved devices when mode and endpoint are available.
What this product does not do
- not HDMI ARC/eARC; not Dolby/DTS decoding; not USB audio; not LDAC; no built-in microphone claim; not a DAC for arbitrary professional digital formats.
- Does not guarantee uninterrupted wireless service through walls, crowds, RF congestion or defective device ports.
- Does not improve a poor recording, repair a damaged socket or guarantee a particular listening volume.
- Does not mix two independent programmes or create independent listener volume unless expressly documented.
- Does not prove compatibility merely because a connector fits or a device advertises Bluetooth.
What to do
Start with one device. Pair and test one endpoint before adding a supported second device or extra cable path.
Keep volume low. Begin at low source and destination volume, especially after switching RX/TX, ANC modes or audio outputs.
Keep firmware and OS current. Updates can improve Bluetooth stability, but use only official vendor updates and do not assume they add unlisted hardware features.
Protect ports and batteries. Grip connectors by housings, keep charging contacts dry and store the product away from loose metal objects.
Confirm active codec or mode. Use the host menu or product display when available. Marketing names do not prove what was negotiated.
Dry before charging. After sweat or a splash, wipe and air-dry completely before returning earbuds to a case or connecting USB power.
What not to do
Do not assume version = feature. Bluetooth 5.x does not automatically mean aptX, LDAC, ANC, multipoint or microphone return.
Do not force connectors. Stop if a plug does not align or fully seat; check direction, port type, case clearance and debris.
Do not charge wet hardware. Moisture plus charging contacts can cause corrosion, heat or failure.
Do not use ANC as protection. Noise cancellation does not certify safe exposure in factories, workshops, shooting, aviation or other hazardous noise.
Do not pair while driving. Configure calls, volume and source switching only while safely parked.
Do not invent reset gestures. Use this model manual; similar HiTune and Bluetooth adapters use different button timing.
Battery, charging and realistic runtime
Power method: Micro-USB power/charging, not USB audio. Use a stable 5V source and keep digital and analogue cables separated from noisy power adapters when possible.
- Published runtime is normally measured under controlled conditions; high volume, ANC, premium codecs, calls, displays, cold weather and weak signal can shorten it.
- Lithium batteries age. Lower runtime after repeated cycles is normal; swelling, leakage, excessive heat or odour is not.
- Use compliant cables and power sources, keep ventilation clear and disconnect if the product becomes unusually hot.
- For long storage, avoid leaving the battery empty for months; recharge periodically according to the supplied manual.
Warnings and limitations
- Hearing: start at low volume, take listening breaks and reduce level if you notice discomfort or ringing. ANC is not hearing protection.
- Situational awareness: do not use isolating audio or ANC where hearing traffic, alarms, announcements or instructions is important.
- Battery: do not crush, puncture, burn, short, disassemble or charge a wet/swollen/hot product. Stop use if odour, leakage or deformation appears.
- Children and pets: keep earbuds, tips, adapters and cables away from small children; small components can be a choking hazard.
- Aircraft: follow crew instructions, use only permitted seat audio sockets and keep wireless functions off whenever required.
- Driving: pair and adjust while parked. Hands-free capability does not remove attention or legal obligations.
- Connections: use only low-level headphone/AUX or stated optical/USB interfaces. Do not connect analogue audio ports to mains, speaker-level or unknown industrial signals.
Troubleshooting and reset
No pairing. Move endpoints close together, charge/power both, disconnect competing saved devices, verify TX/RX direction and restart pairing.
Audio but no microphone. Confirm RX mode and the built-in-microphone call path; TX mode does not return a headset microphone.
Drop-outs. Reduce distance, remove body/metal obstruction, move away from crowded 2.4GHz sources and test one paired device at a time.
Delay. Use a low-latency mode only where listed, confirm both endpoints support the needed codec and compare with a wired path.
Only one side/listener. Test the first endpoint alone, then pair the second using the model-specific dual-pair sequence.
Model-specific reset. Clear pairings through the model’s documented control sequence and remove old Bluetooth records from the endpoints. Power-cycle after changing TX/RX or optical/AUX modes.
At a glance.
- Product
- UGREEN optical/AUX Bluetooth transmitter and receiver
- SKU / colour
- 70158 / black
- Bluetooth version
- 5.0
- Audio interfaces
- Optical S/PDIF input/output and 3.5mm AUX input/output
- Wireless roles
- TX and RX
- Codecs
- aptX, aptX HD and aptX Low Latency listed; common fallback depends on endpoint
- Dual link
- Listed in TX and RX
- Runtime
- Up to 15h TX / 12h RX
- Charging time
- About 3h shown in media
- Power port
- Micro-USB; power only
- Calls / microphone
- Not verified
- Optical format guidance
- Use compatible stereo PCM; compressed surround decode not claimed
- In the box
- Confirm SKU on the product/box rather than buying by family name alone.
Confirm transmitter versus receiver direction and every wired connector.
Confirm microphone/call need, desired codec and simultaneous-device need separately.
Check whether the source device supports Bluetooth audio, not only Bluetooth peripherals.
Inspect the sealed package on arrival and retain the manual for the correct reset and control map.
Numbers are model listing or exact-media figures unless marked unverified. They are qualified laboratory maxima, not universal guarantees.
Questions buyers ask.
What exactly is UGREEN 70158?
It is a rechargeable Bluetooth 5.0 transmitter/receiver with optical digital and 3.5mm analogue audio paths for televisions, headphones and home audio.
What is the difference between TX and RX mode?
TX sends sound from a TV/player’s optical output or 3.5mm output to Bluetooth headphones/speakers. RX receives phone/tablet Bluetooth audio and outputs it through optical or 3.5mm to an amplifier, powered speaker or receiver.
Which codecs are supported?
The listing and media identify aptX, aptX HD and aptX Low Latency support. The active codec still depends on the paired endpoint; SBC fallback should be expected when the other device lacks aptX. LDAC is not claimed.
Is there a guaranteed low-latency mode?
aptX Low Latency requires compatible support at both ends. “No lag” is not repeated as a guarantee; TV processing, optical settings and headphone codec selection can still affect sync.
Do calls and the microphone work?
No microphone or call profile is for SKU 70158. Treat it as programme-audio equipment, not a hands-free car kit or headset-microphone bridge.
Can TX or RX mode use two Bluetooth devices at once?
Dual link supports two devices in TX and is listed for RX. It does not mix sources or create independent volume and codec behaviour can change when two listeners are connected.
What battery life should I expect?
How is it charged or powered?
Micro-USB power/charging, not USB audio. Use a stable 5V source and keep digital and analogue cables separated from noisy power adapters when possible.
Which devices are compatible?
Optical S/PDIF or 3.5mm sources in TX; optical or 3.5mm destinations in RX; Bluetooth headphones, speakers, phones and tablets with a common supported codec.
What should I do if pairing fails?
Clear pairings through the model’s documented control sequence and remove old Bluetooth records from the endpoints. Power-cycle after changing TX/RX or optical/AUX modes.