Indeed, I found a heavy hiss covering up the audio on KOMO AM the other day when I tried in on the home boombox I use all the time, at my place between Shoreline-Edmonds. I haven't tried it lately, just been sampling them on the car radio, where they sound fine. But at home the other day, KOMO sounded like it needed me to re-orient the way the receiver sits another 90 degrees, which I would only expect to have to do for a weak or distant signal station, and which I have never had to do before for 50kw KOMO.
I'll try to remember checking it again to see if there's an improvement this week. I only noted it after reading comments about the signal on this site, and was surprised to confirm a heavy hiss covering up the audio where it had always come in as clear as anything before. Seemed like the hiss beat back the signal and make it weak. Had to turn the volume up to twice as high as the other stations, if I wanted to endure the noise level mixed in with their weakened signal.
I did not find hiss and reception changes to other stations on that receiver, so it's not me, it's them, as far as I can determine. Of course, the Seattle City Light and Snohomish County power lines are overloaded with interference when driving on the arterial streets around here, especially around traffic signals, or on the power lines that follow Fircrest and part of 100th St in Edmonds.
I also get some strange signal interplay during the daytime from the nearby KCIS tower, which seems to put KVI on top of CBU on AM690 around my neighborhood, and it also put a loud heterodyne-type whine on the AM1090 signal during the day, when I used to listen to it when it was KPTK. It went away after sunset, when that tower site shuts off. I don't know if the folks at Crista have anything to do with mucking things up for KOMO, but I do feel their tower does some strange stuff at several other spots on the AM dial, and not just as expedted at AM 1260. Doesn't help improve their ratings any, or convince the neighborhood to vote Republican, if there's anything like that behind it.