I'm not familiar with the DVD player you're using (Yamaha DVD-750?). Typically 7.1 analog inputs are included on receivers to provide for future 7.1 outboard processing (which as far as I've seen is still "future") and for doing high resolution multichannel audio using direct radiating surround back speakers as the surround channels (connecting the surround outputs of a DVD-Audio or SACD player to the surround back inputs of the 7.1 analog in). Using the analog output of a DVD player will lock you in to that player's processing - which means only 5.1. The ICBM can't help with that. To use all seven speakers in a 7.1 setup, you'll need to use the RX-V2500's internal processing - which means a digital audio connection from the DVD player for DVD's and using the receiver's digital bass management rather than the ICBM.