iPhone 7 Sound Not Working? Audio IC Disease Full Hardware Repair Guide
If your iPhone 7 has no sound, especially during calls or voice recordings, it's likely due to a known hardware issue called the Audio IC Disease. This is a common fault in iPhone 7 and 7 Plus models and is caused by a weak or broken connection under the Audio IC on the motherboard.
Symptoms of Audio IC Failure:
- No sound during calls – either you can't hear others or they can't hear you
- Speaker button is greyed out during calls
- Voice Memos app crashes or doesn't start recording
- iPhone becomes slow or freezes when opening call or recording functions
- No sound at all from speaker or earpiece
Recommended Tools:
- Microscope (at least 40x zoom)
- Hot air station (Quick 861DW or similar)
- 0.01mm jumper wire
- UV mask, flux, and tweezers
- iPhone schematics + ZXW or JC Drawing Tool (optional but helpful)
✅ Possible Causes:
- Faulty Audio IC (Intel 338S00105 or 338S00220)
- Broken or disconnected C12 Clock Line under the Audio IC
- Cracked or damaged logic board traces or pads under IC
- Shock or water damage causing internal layer cuts
Hardware Repair Solution – Reball or Jumper Audio IC
- Remove the Audio IC from the motherboard using hot air and microscope
- Check if Pad C12 or C10 is damaged – if yes, create a jumper to its original CPU point
- Reball the IC and reattach it securely
- If the IC is physically damaged, replace it with a new one
📍 Most common jumper:
C12 → Jumper to R1103 or relevant CPU point
Software Checks (Before Hardware Repair)
- Try restoring the iPhone in DFU Mode
- Check logs via 3uTools to see if Audio IC is detected
- If you get restore errors like 4013, 9, or 21, it can also point to Audio IC failure
Note:
This is a motherboard-level hardware problem, not just a speaker or software issue. Replacing the speaker or charging flex will not solve it.
If you need help with Audio IC Reballing, Jumper diagrams, or schematic images, feel free to ask. I can guide you through the entire repair process step-by-step.