Hi, I've run into some problems with my 4-year old B&K AVP4090 preap and B&K AV5000 amp. Recently, during 5.1 playback, the unit starting abruptly cutting out. High volume quick bursts of static followed, until I could get the remote to turn off the preamp. It seems to happen after the unit has been playing awhile, but has never happened before. The local dealer has been of little help, but the problem seems to be happening more frequently. It appears to be source independent since it happens with my DVD or XBOX (5.1 adaptor). The problem does go away for a while once the unit it turned back on, but will return.