I have an AM21 connected to my HR21 receiver and a couple of my OTA HD feeds just won't come in anymore (NBC 48-1 out of Huntsville, AL and CW 15-1 out of Florence, AL). I had no problem getting these stations from October of last year when I signed up with DTV through the beginning of this summer. But for the past couple months, I can't get a signal anymore. I let it go for a couple months because there's nothing on those channels for me during the summer. The last time I remember watching NBC this summer was right when Conan took over for Leno. I live only 7 miles from the mountain that has the NBC station tower. When I do the signal test from within the HR21 for my antenna stations, it never acquires a signal for that station but the guide information and shows are all there. But I always get a 771 error (searching for OTA signal or something to that effect). All the other local HD stations are on that same mountain as well and I get them with no problem except for that CW 15-1 in Florence which is about 40 miles away so I'm not quite as concerned with that, but I still used to get it in without issues. It won't acquire from the HR21 antenna signal test either. In order to make sure my cable hasn't messed up, I unplugged the cable between the antenna and the AM21 and plugged it straight into my TV. All my channels were there with a signal meter in the 80s and above (CW 15-1 in the 40s). I remember last year when I got the antenna, the signal meter on the TV would say my reception for the local stations was in the 90s and above (CW 15-1 in the 50s), so I'm not sure why it dropped 10% on a couple channels, but they are still really high I thought. So anyway, I'm trying to find out why I'm not getting my NBC 48-1 through the AM21 anymore since my signal meter on it is so high when not going through the AM21. The AM21 just can't acquire it. I had a DTV tech out yesterday and he inspected my OTA antenna and replaced some connections with some higher quality ones but still no acquisition of the two stations through the AM21. The tech just said that the AM21 drops the reception of the signal by 20% or so and it just must not be letting the station through. This shouldn't happen when I have a 55 mile OTA antenna (the DB4) and the mountain with the towers is in clear view of my house only 7 miles away. The only thing I can think to try is putting an amp at the antenna to boost my signal even though it is high already. I've tried resetting the settings on my antenna on the DTV equipment a few times, to no avail. Does the AM21 have firmware updates or anything? Could a firmware update I got for the HR21 back in June be the culprit? Does anyone else have any ideas that I could try? Thanks!