It could be position related (not target object related, but where the target is in the sky).
If so, it sounds like intermittent connection, and the ASI firmware not recovering from it gracefully -- it should check after reconnecting if tracking had been turn on after reconnecting.
Try strain relieving both ends of the cable. Double back the cable at the ends and tie-wrap or velcro it to something solid. See if the problem goes away.
Another possibility is that at some directions the mount is pointed to, you could be getting inteference from the WiFi signal. Try to steer any unshield USB cables away from WiFi antennas. Avoid the flat ribbon cables from ZWO at all cost.