On my Holy Stain, I can use Fuzz mode just fine with a standard 9v AC adapter, but the clean mode is barely audible, and the OD mode sounds like what your describing. Using the EHX 9.6v adapter fixes the problem. If you have another EHX pedel that came with a 9.6v power suppply, try that out, or hookup a 9V battery to see if that fixes it. That’ll let you know it’s a power issue. Good Luck.