Anything I can check with a voltmeter? I can't find any burnt parts, visually everything looks okay.Arcing-large amounts of dc , relay won’t click cause the amp is probably in protection.
The Marantz 250 is a nice sounding amp, but the design is fraught with problems. Fixing it (and applying the essential upgrades) is not for the inexperienced and you've almost certainly got way more trouble than can be fixed with a DVM. Suggest locating competent tech (maybe somebody here on AK) ASAP.
Was listening to music then one channel cut out and I saw this part arcing in the area circled. I shut it off and let it sit awhile, tried turning it back on the protection relay doesn't click anymore? Not sure what to check any ideas?
I'm doing one right now that had this happen....Bob
This is not a simple put in some caps and a transistor fix.