SHO Boost - noisy when off, whistles when engaged

I really can't figure out what i'm doing wrong here. I ordered a 3-pack of RullyWow Fo Sho pcbs to mess around with. I threw the first one together with parts I had on hand, which are all correct but not normally my first choice (carbon resistors instead of metal film, big mylar cap instead of the metal film box ones). Then I did it again with the first choice parts, with the same result. When it's just this between my guitar and amp but turned off, I get lots of buzzing/humming noise in my signal. If I engage it, I get a high pitched whining/whistling sound. Both these things happen whether it's in an enclosure, out of one, or hooked up to the pedalpcb testing platform.You can hear the guitar somewhat through the whine, and the pot crackles when turned just like the SHO, but after doing two with different components I'm clearly doing something wrong here with the basic board population. Anything obvious that you guys see? I included the switch wiring (rat's nest) and a pic of one plugged into the testing platform, too.


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