Guitar Gear Forum

I got a pair of Mackie HR624mkIIs from a friend for free this weekend because he upgraded to 824s and one of the 624s has an issue where the sound will gradually fade out during playback, then come back after a rest period. I haven't plugged them in yet to do my own testing, so I don't have 100% confirmation of the behavior, but the description that he gave me makes it sound like an overheating problem.

I can't find anything online about this being a known issue with 624s, so I'm guessing that I just have a random component that went bad (blocking cap, maybe?)

Anyone seen this issue before or have any suggestions on the best place to look to fix the issue?

Check or replace C76 on MK2 (C65 on MK1). Should be an electrolytic cap (4.7 63v). They just dry up and cause the unit to die out or not turn on at all.

Also I'd check solder connections on the boards. Notorious for bad solder.

Thanks for the info. I did some testing last night, and under heavy bass conditions there's a buzzing sound from the bad monitor and under extreme bass the power LED cuts out with the sound. It sounds like a bad connection somewhere, but I think I'll replace c65 while I'm in there as it's a known issue.