I acquired this Marantz 1180DC--- All pots & sliders have been full range of motioned a gazillion times (can feel the wire wound windings) all input functions work. Speakers 1 & 2 & both operate---EXCEPT---when volume pot goes above approx 1/3 volume, the output to any speaker combination goes intermittant (Off & on for approx 1/2 second cycles.) popeyeseaman@aol.com