Good day all! First post, well other than my intro. Long time lurker though. Joined because the Bryston circle is large and very active. I cannot find much info on the D250Z multi channel amplifier. I am interested in maybe purchasing one on line, but the seller says 4 channels, out of 8, may not work. And that this could be fixed under warranty. I have my doubts about the warranty fix. Is this true? I know Bryston does 20 year warranties, but anything after 2006 you need a receipt from an authorized seller. Any help is welcome. Thanks in advance!