Hi rbatfmi,

Out of 25 boards with the EPCQ32A , 4 works well (16%), configuration fails on the others.
We used the SO8 package (AS x4). We soldered 0805 10pF C0G capacitors between pins 2, 3, 5 and GND (pin 4). i.e. between D0, D1, D2 and GND. After this modification, the configuration works on all boards (tested at room temperature, at approx. -10C and at approx +50C). We do not like this solution, but we could not find a better one. It is not clear to us what causes the problem and why these capacitors solve the problem. An hypothesis is that the EPCQ-A might have faster edges than the EPCQ devices and that the capacitors increase the rise/fall times. This, in turn, would improve the quality of the signals at the other end (the FPGA side) of the tracks. Other ideas?
A reply with more details is currently awaiting approval (due to the attached files). I expect it to be published over the following days.