scottyo78

That's weird. :o I've never, ever had a problem with my HD500 (which I've had now for 6 months), nor with my PODXTLive. Both Tuners work great as "tested" by my ear and my bandmates. Not saying you specifically are not having a problem though. :P My best guess is (as stated above) the string is old and flat thus not giving out good vibrations. Also being that the third is un-wound can be problematic for it's pitch. Seems to me the calibration and reference is set with a crystal circuit. The Tuner can be set differently per page 1-4 in the Manual. "Reference (Knob 1): If you’d like to tune to a reference other than standard 440Hz, select from 425 to 455Hz.".

I agree with you on the compressors not being stellar. The ones' I'll sometimes use are the Red, Blue and Vetta. I do like the Tube Drive (Chandler) model though. You should be fine running "a pedal" into/before the HD500. Don't ever run an output from an amp into the HD500 though. I'd start with your (additional) pedals' gain way down then slowly bring it up while listening. If any distortions you may want to disable the effects 1 at a time within your preset on the HD500 then when it sounds correct to you, adjust the effect level.