so i managed to drop my 7300 off the desk a few weeks ago, not a huge fall maybe 18 inches onto carpet but ever since then the tx audio sounds absolutely horrible on SSB. people keep telling me i sound like im underwater or something is buzzing in the background. rx is completely fine, everything looks normal on the display, power output is still hitting 100w, SWR is fine, its literally just the transmitted audio that went to garbage.

i opened it up and had a look around and nothing is obviously broken or cracked that i can see. i checked the electret mic element in the hand mic and it tests okay with a multimeter. im wondering if maybe something on the audio board came loose or a cap took a hit but i honestly dont know where to start on this one. has anyone dug into one of these for tx audio issues specifically? i dont really want to send it to icom if i can help it because the repair turnaround seems insane right now

first thing id do before poking around inside any more is rule out the mic itself more thoroughly. multimeter continuity on the element isnt really a full test — plug in a different mic or even just a headset and see if the problem follows the radio or stays with the original mic. sometimes the connector on the hand mic takes a hit when the thing falls and youll get intermittent contact that reads fine cold but acts up under load.

if its definitely the radio and not the mic, the most likely casualty from a drop like that on that board layout is going to be around the mic amp stage. on the 7300 the audio processing goes through the FPGA but the analog front end before that is where id be looking. check for any obviously cold or cracked solder joints around the mic input jack on the main board, that area takes mechanical stress pretty directly. reflow anything that looks even slightly suspect. ive seen guys fix similar issues just by reflowing a few joints that looked totally normal to the naked eye but had microscopic fractures.

yeah the mic swap suggestion above is dead on, do that first. i had a similar thing happen with an older 746 pro (different radio i know) and i spent like two hours inside the thing before realizing the coiled cord on the hand mic had a broken wire right at the strain relief. drove me crazy.

also worth checking your menu settings havent somehow gotten scrambled — i know it sounds dumb but a hard knock can occasionally do weird things and if the tx bandwidth or mic gain got changed it might explain the underwater thing. probably not it but takes 30 seconds to check so why not