Based on what I could glean from your post, if this is happening across multiple phones, or full phone restores don't help, or replacement buds didn't work either, then either the charging case or firmware state tied to the case is extremely likely to be the root cause.
Since you’ve already done the obvious (multiple resets, full device restores, replacement buds, different iPhones), you’re clearly past normal troubleshooting. When AirPods stay connected but output no sound, it’s almost always one of three deeper issues: audio routing conflicts, firmware/state corruption inside the AirPods case, or sensor/ANC subsystem glitches that don’t reset with standard pairing resets.
What I suggest that you try:
Force-reset the internal audio routing
- Put AirPods in ears.
- Start playing audio.
- Open Control Center → AirPlay icon.
- Manually switch output to: iPhone speaker, then another device if available, and then back to AirPods.
- Also go to: Settings → Accessibility → Touch → Call Audio Routing → set to Automatic (not Bluetooth Headset).
Disable Automatic Ear Detection (test for sensor failure)
- Settings → Bluetooth → AirPods (ⓘ)
- Turn OFF: Automatic Ear Detection
- Then test playback. If sound suddenly works consistently, the optical sensors may be misbehaving or firmware is glitching.
3. Clear hidden iCloud device state (aka, deep pairing reset)
Standard resets don’t remove the iCloud pairing profile. Try a deeper wipe:
- Forget AirPods from ALL Apple devices on your Apple ID.
- Settings → Apple ID → Find My → Devices → remove AirPods.
- Put AirPods in case.
- Leave lid open.
- Hold button ~15–20 sec until LED flashes amber → white.
- Close lid for 30 seconds.
- Restart iPhone.
- Re-pair fresh.
Check Spatial Audio / Personalized Audio corruption
- Settings → AirPods → Spatial Audio → turn OFF completely.
Also remove any Personalized Spatial Audio profile if present.
Toggle key audio subsystems
- Settings → Accessibility → Audio/Visual → toggle Mono Audio ON then OFF.
- Disable Dolby Atmos (Music settings).
- Disable Head Tracking.
- Turn off Conversation Awareness / Adaptive Audio temporarily.
Case firmware issue (strong possibility)
Since you replaced the earbuds but problem persists, as I mentioned earlier, the charging case is a prime suspect. The AirPods firmware actually lives partially in the case, and corrupted state inside the case can survive resets.
- Fully discharge AirPods AND case.
- Recharge to 100%.
- Leave plugged in near iPhone overnight to force firmware sync.
If you want, tell me:
- Does audio resume if you toggle ANC modes?
- Does media show as playing but silent?
- Does phone call audio work while music doesn’t (or vice versa)?
- Does removing ONE earbud restore sound?
