Auto focus with Vivitar slide projector just keeps on focusing?

If your Vivitar slide projector's autofocus feature is continuously adjusting without stopping, it may be due to a malfunction in the autofocus mechanism or a dirty lens or sensor. Check for any obstructions or dirt on the lens, and clean it gently if needed. Additionally, ensure that the slides are properly placed and not causing interference. If the problem persists, it may require professional servicing or repair.