Some progress. Disabling Realtek Audio in Device Manager makes the system stable again: "System interrupts" no longer maxes CPU, my Bluetooth mouse is visible, the system shuts down and restarts cleanly, and I can reenable the Realtek PCIE CardReader device without issues. Also, I realise now that the problems started after completing a Zoom call, which probably relates to a known Realtek Audio/Zoom bug being discussed at the moment (here). Unfortunately I already had at the time of the failure the "fixed" 9369 driver. Ah, finally: Uninstall+Reinstall of the Realtek Audio driver appears to have resolved. Note that I first had to disable the device in Device Manager as the system was too unstable for any driver installs to succeed. (I had also updated the Realtek PCIE CardReader driver, but don't know if this was a factor.)
Hi, My 2-month old XPS 15 9520 has suddenly gone a bit sad. It had been working 100% fine until this afternoon it popped up an error about audio, then my Bluetooth mouse disconnected, then Windows wouldn't restart (endlessly spinning shutdown wheel). On power cycling, still no audio, no Bluetooth mouse, and in Device Manager the Realtek PCIE CardReader was showing an exclamation mark. In Task Manager, System interrupts is showing very high CPU. Probably related to this, Windows Update/Dell Update/driver installs/shutdown all get stuck. I installed BIOS update 1.5.0 the day before, but had no problems at the time. Any thoughts?
XPS 15 9520 suddenly misbehaving, "System interrupts" high CPU usage