My personal code of conduct is never throw in for a deal you can't honor, and negotiate the margin up front, try to make it a fair win win.
Some people do business differently, things happen, but this deal was such small potatoes I am a bit confused why no communication is happening.
Fair...
My experience with the chinese cps1 is if it seems like a knock off part it is.
The only way I fixed mine was a full proper recap with correct audio amp and swapping the knock off parts.
Plus reburning the eproms.
I know they seem like a deal but by the time I corrected all that it wasn't.