It actually sounds like your bottom microphone might be the issue. On the iPhone SE (3rd gen) there are multiple mics, and different apps use different ones. The Camera app (especially when recording video) often uses the rear or front mic, which is why your recordings there may sound fine, while calls, Voice Memos, and most apps rely on the bottom mic. If that mic is damaged or partially blocked, you can get the crackling/static sound you’re describing.
A couple of things you could still try before taking it in:
- Test the mics separately
- Record a Voice Memo (this uses the bottom mic).
- Record a video with the rear camera.
- Record a video with the front camera.
- If only Voice Memos sound bad, that strongly points to the bottom mic.
- Remove the case/screen protector temporarily
- Some cases partially cover the bottom mic holes and cause distortion.
- Gently clean the bottom microphone holes
- Use a soft brush or wooden toothpick to clear lint from the tiny holes near the Lightning port. Pocket lint can cause crackling.
- Check noise cancellation settings
- Go to Settings → Accessibility → Audio/Visual → Phone Noise Cancellation and toggle it off/on to test.
- Reset all settings (doesn’t erase data)
- Settings → General → Transfer or Reset iPhone → Reset → Reset All Settings.
If the Voice Memo test still produces crackling, it’s very likely a hardware issue with the bottom mic. At that point, the best option would be to have it checked by Apple Support or an Apple Authorized Service Provider, since the mic assembly may need repair or replacement.
Hopefully one of the tests helps narrow it down.
