Not cooking USB3 ports on Linux?

I'm still using an 11" Linux notebook bought in 2016 as a beater and "kitchen workstation". It has a single USB3 which works fine in itself but has a tendency to get cooked. I say cooked because it will happen almost inevitably when I/O over it gets too intensive. As an example: yesterday I copied about 260Gb twice using zfs send/receive (comparable to rsync), from an internal HDD to an external SDD and later to an external HDD. Peak speed was about 70MB/s. When I copied a much smaller amount from an internal to an external SSD the operation hung, forcing me to power-cycle the machine because there was no way to kill the process(es) involved (the copy had reached about 141MB/s at an earlier point). The same thing had happened a few days earlier trying to format that same external SSD to NTFS. I never tried this machine under MSWin so have no idea if this is a hardware issue or rather something at the OS level. The only diagnostic info I get is kernel oopsie dumps in the syslog, about a process being hung. Kernel in use is 4.14; I tried newer ones but 4.14 seems to be a sweet spot. Any idea what this can be and how to avoid it?