Symptoms
- No bass or rumble from movies or music
- Subwoofer's power light is off or blinking
- Rest of the sound system works fine
- Bass cuts in and out
Likely causes
- CommonSubwoofer not receiving power or set to standbyMany subs auto-sleep when no signal is detected and need a strong enough signal to wake.
- CommonSubwoofer volume or crossover set too lowA low gain knob or crossover frequency set incorrectly can make bass nearly inaudible.
- CommonLoose or wrong cable connection (wired or wireless)A disconnected RCA/LFE cable or unpaired wireless transmitter cuts bass entirely.
- PossibleReceiver/soundbar channel settings not sending bass to the subSpeaker size or crossover settings in the receiver menu can route bass elsewhere.
- Less commonFailed internal amplifier in the subwooferA dead internal amp will leave the sub completely silent even with correct settings.
What to do
- Check that the subwoofer is plugged in and its power light is on (not blinking, which often means standby/no signal).
- Turn the subwoofer's volume/gain knob up about halfway and check the crossover/frequency dial is set to a reasonable range like 80–120 Hz.
- Confirm the wired connection (RCA/LFE cable) is fully seated, or re-pair the wireless subwoofer following the manufacturer's pairing steps.
- Play content with strong bass, like a movie action scene, since some subs need a strong signal to auto-wake from standby.
- In the receiver or soundbar's audio setup menu, confirm speaker sizes are set to 'small' so bass is routed to the subwoofer.
- Move the subwoofer to a different spot temporarily, since corner placement or being too close to a wall can mask or muddy bass.
- Test with a different source device to rule out a source-specific settings issue.
- If still silent, try a different cable to rule out a bad wire.
Tools and parts
- Spare RCA cable (for testing)
Subwoofer RCA cableSearch: “subwoofer rca cable”
When to call a pro
If the sub shows power but never produces sound with a confirmed good cable and correct settings, the internal amplifier has likely failed and needs professional repair or replacement.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.