Hi everyone, I have an odd problem that I just can't get my head around. Ive just bought a secondhand rusty box in pristine condition. It's the centre positive power version and sounds amazing, but....the second I put anything in front (compressor, envelope, tuner) the signal cuts out. I've tried various cables/buffered vs true bypass/power options (powering the preceding pedals separately) but nothing seems to work. I'm stumped....I'm hoping someone can offer some suggestions and yes, I'm quite prepared for the answer to be embarrassing. Thanks in advance!