History: I purchased a ZFrontier F&T 1916 a few months ago. I swapped switches, and the PCB tested fine before reassembling into the case. After installing keycaps and connecting to my computer, the board couldn't be recognized as a USB device.
I tried all sorts of tricks, including flashing with an ISP connected directly to the board to bypass USB. The programmer sees the Atmel chip, but USB no longer works.
I attempted to contact ZFrontier and Sylvester with no success. At this point I was willing to purchase another of their PCBs. Both replied in fragmented English, then stopped replying.
On further investigation, I determined that 2 of the 4 screws holding the large brass weight into the case were too short, leaving the weight to move around. There was no insulation between the weight and the exposed back of the PCB. My guess is the weight shifted while the board was powered and shorted some component on the PCB.
I took a chance on Hineybush's H87a PCB. It fits nearly perfectly, save for a shorter USB "neck". This means I will have to open the case to unplug the cable. I'm ok with that for now.
Secondary LPT: Stop buying from ZFrontier. They're selling poor quality hardware at high prices with zero support. They suck.
https://imgur.com/a/hTxSEgE
