Tommy volume issue

[P51994]

Hi there ! I just build the Tommy III .
Everything sounds great except when the volume pot is tune after 12 oclock, there is a unpleasant whistling that killing my remaining ears !
I already noticed this problem on other pedal.
Is it a potentiometer issue ?

The general question is : why sometimes we have these whistling noises when the pot is turn fully clockwise ?
Thanks !

 

[temol]

It is most likely an oscillation (excitation). For example - this is a situation in which the output signal of one stage enters one of the previous stages. There may be various reasons - wiring, coupling. Often, this issue is associated with two controls - GAIN and VOLUME.

Check your wiring - maybe IN/OUT wires are too close? Or maybe too long?