Switch Control Mode randomly keeps switching back to Item Mode on iPad

My father is a quadriplegic and relies on Head Tracking to operate his iPad 10th gen (MPQ03X/A). Since the iPad OS 18 update the Switch Control Mode is changing itself from Head Tracking to Item Mode, seemingly at random. We cannot identify why this may be happening. This did happen occasionally in iPad OS 17, maybe once a week. But now it is happening several times a day.