Crash when there is still some data in buffer and we restart the ESP device.

<img width="583" height="91" alt="Image" src="https://github.com/user-attachments/assets/149cd768-d406-445e-a8c6-91bfdfec497a" />

Uh oh.
Also, there are Serial printouts in ISRs that make the code crash when we try to print an error. This is a reocurring pattern. Should we discuss a fix?