Hey Rojo, I noticed the same symptoms, although mine don't happen till after an hour or so of driving.

On my empeg, the audio just quits, but everything else functions fine... Pulling the unit out of the dash to reboot it will fix it, but only for a few minutes. However, putting the Empeg in front of a vent blasting cold air will fix it for half an hour or so, so it looks like the audio circuitry is overheating and cutting out - btw, my digital temp sensor doesn't work, so one of the audio components must be hitting an internal temp cut. Turning down the volume helps too; I was running around 0db most of the time, using a 4V Alpine amp input.

My engine blew, and my amp was stolen while the shop was fixing the engine, so I won't be able to mess with this for a bit, but let me know if you figure anything out.