The 1960 8p Gigabit CL4 PoE 4p SR2.5 CL6 PoE PN S0F35A is what you are looking for from Instant On portfolio.
Random problems are the worst kind to troubleshoot.
It can be cables, PoE power, ...
It is very strange for Aps to get into unresponsive state. Can you see what is happening on switch ports? If you still have support available, I'll suggest to open a TAC case so support can look into the problem.
Best, Gorazd
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Gorazd Kikelj
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