Yamaha DVD-C750 Multi-disc DVD Player

I recently purchased a Yamaha DVD-C750 changer for it's ability to play SACDs and DVD-As and it's multi-disc convenience.However, it has turned out to be extremely inconvenient because the "Resume Play" function didn't work. Anytime a DVD, SACD, or a CD was stopped, it returned to the beginning of the disc when play was resumed. It also recognized DVD-As as DVD videos. I returned the unit and the replacement unit had the identical faults. Subsequently, I exchanged this unit for a Yamaha 6760 DVD changer.The resume play function on this Changer didn't work either. I have sent two(2) e-mails to Yamaha, and have yet to get a response for what appears to be an inherent defect on all Yamaha DVD changers.