so this has been driving me nuts for about two weeks now. my 7300 started acting weird where receive is just... really weak. like i can barely hear stations that were perfectly readable before. TX power looks normal on the meter, ALC is behaving, SWR on my antenna is unchanged. done all the usual stuff, checked the coax, swapped the feedline at the shack end, even tried a dummy load with a handheld next to it just to confirm its not the antenna.

noise floor looks about the same on the waterfall which is confusing me because if it was a preamp issue or front end damage i'd expect the noise floor to drop too, right? but signals that should be S7 or S8 are barely moving the meter. im starting to wonder if its the AGC doing something weird or maybe one of the IF stages. anyone had something similar with this radio or any icom in general? i really dont want to ship it off to icom if i can figure out what's going on first.

Had something similar on my 746 years ago, turned out to be a bad solder joint on one of the filter board connectors. The symptom was almost exactly what you're describing — noise floor looked roughly normal but actual signals were way down. The way my tech explained it was that the noise floor reading can be misleading because broadband noise couples in differently than a discrete signal going through the full IF chain.

On the 7300 i'd start by going into the diagnostics menu if you haven't already and checking the S-meter calibration settings havent somehow shifted. Unlikely but worth 30 seconds. After that honestly it might be worth pulling the top cover and just looking for anything obvious — caps that look domed, anything that smells burnt. The 7300s aren't particularly notorious for internal failures but they're not magic either. If you're comfortable with a scope you could trace signal through the RF board but if not, Icom's turnaround on depot repairs has actually been pretty reasonable from what I've heard lately, couple months at worst.

check if you accidentally hit the attenuator or turned the preamp off, i know it sounds dumb but ive done it myself more than once and spent an embarassing amount of time troubleshooting before noticing the little ATT indicator sitting there on the display. the 7300 touch screen makes it pretty easy to fat-finger stuff.