The linux-image-5.4.0-1041-raspi version of the Ubuntu linux-image package appears to be unstable.  I've had two of the OSD RPi boards randomly lockup.  The boards recover on their own once power-cycled, but this is the first time I've observed this behavior.  There no messages in the system logs. The logs simply stop at the time of the lockup, and resume on reboot.  I've upgraded all of the RPis to the latest image version (1042) which should hopefully resolve the issue.