I would advise caution about buying unknown pots. Back while I was working at Peavey there was a parade of small potentiometer makers trying to sell us their wares. Apparently in Taiwan (then) and China (now), there are a number of small factories making components and subassemblies for the larger pot manufacturers. These small factories all want to get a share of the big boys business.
Long story short(er) as an engineering manager I was always getting bugged by our purchasing clerks to approve some new no-name pot maker so they could win a prize for cost savings (a couple pennies times millions of units a year adds up)..
I recall one time where the samples looked OK, so I finally approved a 1,000 piece production test. On mixers that used a bunch of pots each, this didn't make a lot of mixers but enough to give the pots a real test. They failed miserably, and the factory ended up removing every pot and replacing them with good parts. The factory was not happy with me, but I just referred their calls to the purchasing puke who stopped bugging me after that.
So yes it is literally possible to find parts too cheap to work. :
I believe this happens to some inexperienced manufacturers who use offshore contract manufacturers and let them source the components with no oversight.
Component quality matters. Good quality doesn't have to be expensive. I think we paid all of $0,07 each for the good pots we used (these were used in small cheap mixers) .
So caveat emptor... I would stick to known brands for pots and switches, whenever possible.
JR
