PSP 1000 seems to charge but won't turn on.

A customer brought in a PSP 1K that I’ve been having trouble with. When the AC adapter is plugged in the orange light comes on to indicate that it is charging, but it will not turn on at all. I’ve tried powering it on with battery and no AC, with AC and no battery, and with both together. Cleaned power switch internals, tried swapping the power switch daughterboard, and of course swapped out the battery. Any ideas? I’ve heard this is a common problem, but I still can’t find any actual solutions online.

Thanks!