Hi - I am having an issue with my Librem 15, where it shut off unexpectedly this morning, while on charge. I have had this Librem for some time, but not seen this before. Likely concidentally, I did hear some rattling a couple of days ago when lifting it switched off, but it had gone away. When I tried to restart it, the power light came on briefly, but went off again - after a couple of attempts, it started and stayed on for around 20 minutes, then the same thing happened again.
After a few more attempts (more than previously), I got it back on and installed lm_sensors to keep an eye on CPU temperature - nothing over 75C. There was nothing obviously useful in /var/log/syslog, and no clear link between the two previous shutoffs. Then it shut off again, after about 10 minutes - the fan had been fairly quiet and there was nothing that should have caused a spike in CPU demand. I have not been able to get it back on for the last half-hour, except briefly to GRUB before shutting off, and the power light is coming on only briefly or not at all.
Can anybody suggest a way of diagnosing further or anything to try, please?