A Bass Module 700 has no left or right channel: it reproduces low frequencies and is placed as a single unit, so a one-sided sound complaint is about the soundbar or its surround speakers rather than the module. Bose's module pages point you to the host soundbar's troubleshooting for audio problems. Use the module's rear LED to confirm it is connected (solid white); if it is, test the soundbar's HDMI eARC or optical path, the TV's PCM output setting and any surround speaker power cords.
Differential
Likely causes of “Bose Bass Module 700 plays from only one side or channel”, and how to tell them apart
- 1
The imbalance is in the soundbar or surrounds
What separates it The bass is even but left or right treble differs
How to confirm Follow the host soundbar's own troubleshooting for one-sided sound, since the module has no channels
- 2
The module is disconnected
What separates it Bass seems to come from only the soundbar, not the module
How to confirm Check the LED is solid white, not dim amber
- 3
A TV format issue
What separates it Only certain programs or apps sound lopsided while other sources are balanced
How to confirm Set the TV's sound output format to PCM
- 4
A cable problem at the soundbar
What separates it Sound changes when the HDMI or optical cable is touched
How to confirm Reseat the HDMI eARC or optical cable at both ends
Before you touch a setting
Record this first — changing settings destroys the evidence
- Whether the module's LED is solid white or amber
- Which programs or sources are lopsided
- Whether the soundbar's other speakers are balanced
Try in this order
0 of 5 completedConfirm the module link
ReversibleCheck the rear LED. Solid white means connected to the soundbar; if it is amber, fix that first because a missing module changes the low-end balance.
Test another source
ReversibleSwitch the soundbar to Bluetooth or a streaming source. If the imbalance disappears, the problem is in the TV or cable path.
Set PCM output
ReversibleIn the TV's sound settings choose PCM as the sound output format and replay the same program.
Reseat cables
ReversiblePush the HDMI eARC or optical cable firmly into both ends, or try the other cable type.
Reset everything
ReversibleUnplug the soundbar and module for 30 seconds, restore the soundbar first, wait 30 seconds, then reconnect the module and wait 15 seconds.
Stop boundary
When this stops being a self-service repair
- !If the module is white and connected and the imbalance stays on the soundbar, follow the host's service route
Evidence ledger
Sources behind this answer
The rear LED states from off to white blinking.
Outlet, cord and LED checks.
Unplug 30 seconds and wait 15 seconds to reconnect.
The label on the bottom of the module.
The module works only with a host soundbar or console.
Refers to the host product's troubleshooting.
Refers to the host product's troubleshooting.
Refers to the host product's troubleshooting.
Tone is set on the host product.
The Connect step for an accessory bass module.
Disconnect the bass module and surround receivers during a reset.
The same accessory disconnect step for the Ultra.
Lists the Acoustimass 300 and Bass Module 700 LED states.
Exact questions
Common questions
Does the module have left and right?+
No, it plays low bass as a single unit.
Who fixes imbalance?+
The host soundbar's troubleshooting steps address balance problems.
Can surround speakers cause it?+
Yes, if they are unpowered or unlinked.
What does the LED tell me?+
Whether the module is connected to the soundbar or has lost the link.
Which output format helps?+
Setting the TV's sound output format to PCM often helps.
Is the module a subwoofer?+
It adds bass to the soundbar system.
Can I move it?+
Yes, within wireless range of the soundbar.
Where do I get help?+
Bose Support for the host soundbar.