KOT dual perfboard power suck

[Martan]

Hey all,

Built a King of Tone dual-perfboard clone. Problem is when I have the left side on everything is fine, but when I engage the right side to stack them, everything goes quiet and then swells back up to normal volume after a few seconds. All is fine again after that. Both circuits seem to function fine on their own.

Any ideas what to check?

Thanks,

Marty