I've been running off an early 2009 Mac mini (2ghz Intel Core 2 Duo; 8 gigs of memory; always on, clean system install, nearly empty internal SSD and the machine is used for nothing but Channels). I have gigabyte ethernet.
Sometimes it works fine, and I can usually watch live TV without any problems, but watching recordings is often glitchy. For instance, for a few days, I'll have no problems watching Jeopardy!, a show that I record at the same time every day under the same conditions. Then, one day, it will suddenly be pretty much unwatchable due to freezing, pixellation, skipping and other issues.
I don't think it's the antenna, or the weather, because to test it, I tried to watch the Jeopardy! recording today, which was unwatchable, but when I switched to watching live (not the recording) it was fine.
Does it seem a faster server would be the way to go?