SamplePad Pro middle bottom pad intermittently sensitive

Second day using the SamplePad (bought refurbished). Upgraded to 1.0.19 firmware, did factory reset.

Middle bottom pad is chronically under-/not-sensitive. Even at sensitivity 8 it does not always register hits at the same force as its neighbors, and when it does, it's at a lower velocity. When tried at global v-curve 8, it only sometimes triggers whereas other pads trigger consistently...

Second question:
The follow-lights only trigger on the two shoulder pads and upper left two square pads. This would be no big deal, but is there a way to set this?

Otherwise, what are my service options for this unit?
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