In the end I arrived at the conclusion that it was probably just the nature of the chip. The led trick did reduce the harshness but it was a bit of a trade off in terms of the volume. The only way I can really describe it is that the signal going in to the chip is loud to the point it's clipping...
Thanks I'll try a different outlet tomorrow and see if it helps. The hiss/white noise is only in the repeats (so when the pedal is engaged and I hit a note), there's no noise other wise.
Thanks Zgrav. Everything seems to work ok besides the fizziness that sits on top of the repeats. I'd socketed the chip and have swapped a couple that I had but it's fairly consistent. I'm thinking that maybe it's just how it is, but have never played an original or built another to compare so...
Hi all, recently finished the dark rift delay and am noticing a overlay of white noise/fizz on top of the repeats. I've searched through the forum and found a suggestion to add a green led between the 7th pin and 3rd pin of the PT2399 may potentially calm the noise a little. I gave that a try...