If I bought an amplifier that was 7.1 channels, and I had software that 7.1 channel - does my 4 year old DVD player have to be 7.1 to get those signals as well? Will the digital output send through a 7.1 signal? How about (theorteically!), a 9.1 or 11.1?

Are there 7.1 DVD players?

Basically - does one ever have to upgrade a DVD player?