Tension,
I don't know what to say. Have you tried a professional contact cleaner (e.g. Tun-O-Wash) on the contacts? Besides that, I know from personal experience that the connectors on certain accelerators are problematic (at best) My dad had an Apollo '030 in his 1200... eventually the connection stopped working alltogether. Yet I've never had trouble with my P5 1260 (tho, in truth, it's in my 1200 tower)
Hope this helps....
