When the SoundLink Flex (2nd Gen) is connected but silent, Bose's article suggests: raise the speaker volume, set the phone's volume to 90 to 100 percent, reboot the Bluetooth device, stay within 33 feet, update the speaker, try a different app and another Bluetooth device, clear the speaker's memory and reset it. On Windows 10 pick the listing with the speaker icon and never the LE one. Apps that use the Headset Profile will not play call audio through the speaker.
Differential
Likely causes of “Bose SoundLink Flex (2nd Gen) connects but has no sound”, and how to tell them apart
- 1
Phone volume set too low
What separates it The speaker is connected but plays faintly or not at all
How to confirm Set the source device's volume to 90 to 100 percent and use the speaker to adjust the level
- 2
The wrong Windows listing
What separates it A Windows PC shows connected but plays no sound
How to confirm Connect using the listing with the speaker icon and not the one with LE
- 3
A call app on the Headset Profile
What separates it Music plays normally but call audio from a calling app is silent on the speaker
How to confirm Try a different app or the phone's regular call function
- 4
An Echo Dot holding other devices
What separates it The Dot and speaker keep failing to find each other
How to confirm Remove other Bluetooth devices from the Dot's memory in the Alexa app
Before you touch a setting
Record this first — changing settings destroys the evidence
- Which apps and devices are silent
- The Bluetooth light color while the speaker is silent
Try in this order
0 of 5 completedRaise volumes
ReversibleTurn up the speaker, then set the source device's volume to 90 to 100 percent to send a strong signal.
Check range and reboot
ReversibleStay within about 33 feet and turn the phone or computer off and on again to clear Bluetooth glitches.
Test another app or device
ReversiblePlay from a different app, then from a different Bluetooth device, to see whether the source is the cause.
Clear the memory
ReversibleHold the Bluetooth button 15 seconds to clear the list, forget the speaker on the phone and pair again.
Update and reset
ReversibleUpdate at btu.Bose.com, then hold Power for 15 seconds with the cable out to reboot the speaker.
Stop boundary
When this stops being a self-service repair
- !If no source plays after a factory reset, request service
- !If the speaker plays nothing and the Power light shows a failed-battery pattern, contact Bose
Evidence ledger
Sources behind this answer
Power, Bluetooth and Shortcut light patterns including failed battery.
The 15-second Power reset and the Volume + and - factory reset.
Four-hour charge, 12-hour playback, overnight charging.
Temperature, charger amp rating and incompatible chargers.
Wait 30 to 60 minutes at room temperature.
Voice prompt and Power button hold.
Wet charging, quick press to power off, tone when powered.
Pairing steps and the 15-second memory clear.
Volume, range, Windows LE listing, HFP versus HSP.
One active driver and two passive radiators, EQ and interference.
Volume, 30-minute auto-off, power off when idle.
Linking, phone assistant and Spotify shortcut.
Firmware 8.2.16 to 4.3.24 and the SE release notes.
The 2026 voice prompt update.
Bose's Speaker Link checklist that lists the Flex 2nd Gen as compatible.
Exact questions
Common questions
What phone volume should I use?+
90 to 100 percent of the phone's volume.
Why is call audio silent?+
Some apps use the Headset Profile the speaker lacks.
What is the Windows LE listing?+
A duplicate entry that does not carry audio.
Does an Echo Dot interfere?+
Yes, if it holds other paired devices.
Can I connect a different device?+
Yes, try one to isolate the fault.
Will an update help?+
It can fix bugs, so update at btu.Bose.com.
Does resetting clear settings?+
The 15-second Power reset does not clear your settings; the factory reset does.
Why does the speaker still show as connected with no sound?+
Bluetooth can hold a connection open even after the actual audio stream has stopped, which is exactly why Bose's list starts with re-checking volume and app choice rather than the connection itself — a green Bluetooth light is not proof that audio is actually routing.