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My Pixel 3a got wet and the earpiece speaker started buzzing/humming/crackling, but it worked and I could hear through it! Everything else worked fine. I bought a replacement earpiece speaker and gasket from here (iFixit) and replaced/installed it. No particular issues. I reassembled after wiping all contacts, and was happy not to hear the buzzing, then realized all I was hearing was the bottom speaker (music or phone). Everything else works fine, that is: proximity sensor, front camera (nothing blocked) headphones (bluetooth and wired) - so it’s not a signal problem, all screen functions. I researched and tried all the fixes I could find. Restart, full Shutdown and restart, hearing aid not on, balance centered in Accessibility. I made SURE the gold spring contacts were oriented properly so that they would touch the 2 gold contacts on the mid-plate. I pressed to ensure the speaker was well in it’s recess and even gave an extra squeeze above the speaker when reassembled (to help ensure the gold springs would make contact. I double checked the anti-static packages and they were labled with the correct parts (I even went to the trash, got them out and triple checked); so, even though the plastic earspeaker frame was a transluscent milky white and not black like all the ones I’ve seen shown, it had to be correct. I’m experienced in disassembling and reassembling smartphones. Help would be appreciated.
[Resolved]. I decided to go in again and see if anything was visibly wrong, like a contact came off during reassembly or whatever. I also intended to remove the motherboard and be sure everything looked good under it, and clean, especially the 3 gold contacts (noticed in the teardown on iFixit) which were on the same plastic where the earpiece speaker’s 2 gold contacts were. I also sourced another earpiece speaker as I wasn’t going to go through this 2nd excursion and not be prepeared. It was much easier to go through the pre-cut and shaped Display Adhesive, as expected. Everything looked good, everything attached, no corrosion under the motherboard or 3 contacts; so, I replaced the speaker… what else was there to do?! I put it all back together, but didn’t glue down the screen. Sadly it didn’t work. I put it in my Spigen case (which actually kind of wraps around the edges and would help the screen stay in place) so I could use it for the rest of the day and try the fix again later. I planned to go in, check the depth of the earpiece speaker in it’s spot (there’s a recess it sits in), see what voltage the 2 gold contacts had, and was considering shimming the speaker with the little blue plastic that protects it when shipped in the package. I was suspicious of that connection. Well… I picked up the phone and was looking at it and noticed a gap in the midframe (it snaps into the back) on the speaker end, where it apparently didn’t lock on well when snapped together the 1st time. I pressed that closed, heard a nice click and tested again… lo and behold it worked. In summary, the original speaker was damaged by the water, the iFixit replacement was probaly good (I had to use needle nose pliers to remove then and they were destroyed). I don’t know why it worked the 2nd time, there was no gap in the base to midframe after my 1st fix attempt, but it did work! Incidentally, while inside the phone I noticed all 3 (that I saw) water indicators were pink. So this is my testament to the build of this phone and it’s apparent water resistance (in my case, the phone went in the washing machine (soapy water) for 5 - 10 seconds before I realized what had happened)), EVERYTHING now works, and hopefully will continue so.
