Physical damage to PLL?

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Has anyone seen issues with the SAMG55 (or similar) where the various clock frequencies are incorrect?  My clocks are derived from a 32.768kHz input, which I have verified is accurate.  I noticed the issue because my console port that was set to run at 115200 baud produced gibberish unless I dropped the speed to ~103k in my terminal program.  I scoped the lines to confirm the issue was coming from my board and not the terminal program or USB->serial converter.  I also scoped I2C lines derived from the same clock, and they are running at ~90.9kHz instead of 100kHz as set.  So the internal PLL output of the chip seems to be roughly 10% too slow.  This is a custom board, and the other units do not have this issue.  All are running the same firmware. 

 

I suspect ESD or similar may have damaged the chip and with it the PLL, and I'm about out of ideas other than swapping out the processor for a new one.

 

Any suggestions before I resort to that?

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Decided to do the sane thing and look at the clock registers, and I do see discrepancies between the good and bad units.  Investigating it now.

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It happen to me in the past that I couldn’t turn on the mcu on the PLL, no matter what I was not able to activate the PLL, only the integrated clock.