Reflashed the phone with no change, so it’s definitely hardware.
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Has Purism support followed up with your issue since you created this topic?
No. I’ve only gotten the original response email, that gives me my issue number and says I’m in the queue.
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I tried reflashing phone. No change in microphones, which I was pretty sure would be the case.
Neither top or bottom mic is working, but headphone mic seems to work fine. I’m looking at the MEMS microphone ICs for top and bottom. I might have to take phone apart and troubleshoot some more. I’m sure I have no warranty, so why not?
Anyone know what U510 on the Librem 5 mainboard is? It would represent a single point of failure for both MEMS microphone ICs, as it appears to transfer the clock signal to both. I don’t see a part number.
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Thought I’d add the latest update to this saga. Support has offered to send me an RMA, and I’m going to send the phone in for service.
I did change the bottom microphone IC with no difference made. I looked at changing the top microphone as well, but was intimidated by all the nearby parts. (Also it wasn’t responding as well to the hot air, and I didn’t feel like cranking it up to higher temps .)
Anyway, I also did some cleaning while I had the phone apart (not super thorough), and when I put the phone back together, both mics were working (with the static again). I think something in one of my prior disassemblies had caused a lack of good connection or short with the ribbon cable to the bottom (USB) board. ??? Anyway, mic change didn’t improve issue. Learned to be more careful in disassembly.
My tech days were done when many things still had through-hole resistors. I don’t think I’m qualified for modern electronics repair. (Getting too old anyway.) I’ll stay a software curmudgeon.
NOTE to other intrepid explorers: if you don’t have a microscope, a magnifying light and a loupe can give you a good view. I used the combo to inspect and clean and found things not visible otherwise.
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