I decided to upgrade to the latest firmware (ver 1.1.3 ) I know that some have said not to do it but the new version was/is supposed to improve the switching. It seems to have done just that. I was having trouble switching from HD to SDTV. I had to hit the source button each time. It now changes without having to do that. Also, It seems to have improved the image on the M1 port. I'm feeding it a Progressive DVD signal. So, not sure it's a good idea for everyone but it seems to have helped me. I still do not notice any audio/video sync issues as was reported by some. Later!