Poor SRECS Reception...
I don't think it's due to the scanners, though. Up until about two weeks ago, I was able to monitor the "Core" (my pet name for the sites that make up the simulcast), Mica Peak, Mt Spokane, and Scoop Mountain sites with a BCD996XT with very little problems, not only mobile, but also at my house. Then something happened. I had heard scuttlebutt that Fancher beacon (part of the simulcast network) had not been actively transmitting until recently. If that is true, then adding the extra simulcast site in the system may have over saturated the Core Simulcast network. This could be leading to the problems recently with scanners getting choppy and having difficulty acquiring control channel. The noise floor and more significant multipath reflections may have increased, bringing decode quality down. Digital communications are highly susceptible to multipath interference and noise floor problems. Simulcast is highly dependent on timing perfection, and an over saturated, reflective simulcast zone might be hard to monitor and use. I also have noticed that the Mica Peak, Mt Spokane, and Scoop Mountain sites, while not as bad, also seemed to have suffered some decode quality degradation, perhaps due to similar noise floor issues due to more RF being transmitted in the areas around them (if that's whats happening). I have been monitoring with two BCD996XT scanners, two separate antennas, two discriminator tapped analog scanners run through software decoding using Unitrunker, and all the results are similar. As of the last two weeks, decode quality is greatly degraded on Core SRECS. It's highly frustrating. I know that if scanners are having problems, it's very likely that actual authorized users are also having similar problems.
It would be very interesting to see what would happen if they turned down about half their simulcast zone radios.
Also, something has changed with the County Fire Main Dispatch. 154.430 sounds like garbage now on analog modulation. I think they have it patched between the digital system and the analog quality has diminished.
Don't blame your scanners quite yet.