Suhr riot stuttering on high notes

[deblacksin]

First of all, I don't think I ever posted here, but I have been reading this forum a ton the past 7 years, since I started DIYing. This place is amazing and so helpful for the new guys all the way up to complete pros. I truly admire this community.

To the chase, I built the Ruckus High Gain pedal from a kit by http://shop.pedalparts.co.uk/Ruckus_-_High_Gain_Distortion/p847124_11520060.aspx
Which is a Riot clone adapted to MarkGor fine adjustments, and it rocked the amp from the first power chord.

The problem is, when I go high on the notes scale, at some point a wierd background decay occurs, rather than smooth notes, and by the high G note (15th fret 1st string) it sound like stuttering or tremolo effect, that is faster and more dominant as I hit a higher note. 19-22 frets aren't playable. The low strings are decaying perfectly smooth.


- it occurs on the modest clipping possible. It's not sensible when the pedal is set to almost clean, but modest crunch will have the same phenomenon.
- more gain=more stuttering.
- it occurs in every clipper mode
- buffered or boosted signal didn't help
- it's not power supply/amp/guitar deal. My FF, Big muff or AC booster don't do it even on much higher gain settings.

Any suggestions?

[Kipper4]

Need more info.
Go here for starters

http://www.diystompboxes.com/smfforum/index.php?topic=29816.0

[NFX]

try changing out the op amps 1 at a time see if you have a dodgy chip, when ive had similar issues with projects it has been a rogue chip.