Help with weird problem in an OD pedal!

[msb69]

I've got an op-amp based Overdrive pedal (true bypass w/3PDT switch) that is acting funny.  First, the on-off LED flickers considerably.  With a battery, the LED even goes all the way out and stays out.  With a 9v adapter, there is mostly just the flickering.  Plus, regardless of power supply, the pedal at times sounds weak and fizzy.

Any thoughts as to the problem?

m

[petemoore]

  Fairly often, yes.
  reading/following the "DEBUGGING" thread is the shortest way known to debugging success.
  A prerequisite to the transfer of useful information and allows the formation of better answers based on questions with the necessary content to form such answers...as well you can begin to see what answers might make sense and find questions to have the DMM 'ask' a non-debugged circuit, or circuit fragment, or even component.