Hello everyone, i have made the EQD Acapulco Gold (El Sol Distortion) circuit a few times on my bread board and the PCB from PedalPCB with both the LM386N-1 x2 and the LM386N-4 x2 . it always has the same problem. if i turn the volume pot up much past 5% it starts to whistle at me and if i keep turning it up the pitch of the whistle will go up. i have made sure each time my components are well with in 1% of the stated value my IC are Juried engineering LM386N-1 from Amazon and LM386N-4 from Mouser . i would appreciate any help or advice on building this circuit correctly thank you for your time.