Guessing that you can't move your DVD to AV1 for some reason, I'll bet you're out of luck. The remote with my DE825 "almost" worked my system perfectly until I added a SONY DSS Receiver. Since it plugged in where my TV used to, I found I had to assign my TV to a USER setting to still use it with cable TV. That screwed up almost everything in my setup. I solved it all by getting a PRONTO, finding the discrete IR codes for my Sony TV and other components, and creating macros to switch everything as I need it. I hit one button for "PLAY DVD" and it switches the TV on, sets it to AV1, turns on the DE825, siwtches it to DVD, turns on the DVD and opens the tray, then leaves me on a control panel with the DVD controls ready. I hit "PLAY DSS" and it switches anythiing it doesn't need off, sets up and routes the DSS signal to the TV, then leaves me on a control panel for the DSS box.
SONY had been very helpful in explaining to me why I wouldn't be able to change the way their remote worked. "You can't do that." they said.