Got a secondhand dbx 286s. Sounds great when it works, but sometimes I'll turn it on and out the gate it will have this diminished signal with extra static on the input. Turning it off and on a few times usually does the trick, but it seems completely random. On top of that, it will sometimes degrade to that issue a few minutes into being on. Other times it will start fine, and be completely fine even an hour later, so it seems like if the issue doesn't arise in the first 15-ish minutes, then it won't occur at all.

Any thoughts? Tried a brand new XLR so that isn't it, and the gain issue reads on the dbx itself so it's not farther in the chain. Haven't tried switching out the power cord...and I doubt it's the mic since it's brand new (shure sm7b).

I might go as far as buying a second brand new 286s to compare, since I could probably use 2 in the future for podcasting anyway.