Need help with system connection


Hello audiogon members, 
I am in a bit of a delima. First my components: Simaudio W5 power amp (2 channel), Earthquake power amp (3 channel), OPPO BDP-105, Marantz AV7701 preamp processor, Von Schweikert VR4, LCR15 center, and NHT surrounds, Benchmark DAC1. Sources: Apple TV, Fire TV. 
I recently purchased the DAC1, which I am using as a preamp connected directly to Simaudio. Love the sound! I am getting the details, soundstage and clarity which was missing in OPPO 105 DAC (more musical). 
Delima: When watching movies using my Apple TV or Fire TV in Dolby Digital, how do I use the FR/FL speakers? Since the Simaudio is now ‘taken up’ by the DAC1, I am only left with the Earthquake 3 channel amp and Marantz to watch movies in Dobly Digital since DAC1 does not play that coding. 
My 3.1 channel works - but how do i run the signal through the DAC1 for the FR/FL channel. Even through the sound will be out of sync, I’ll be okay. Any suggestions would be greatly appreciated. Thanks, ghulamr
128x128ghulamr
Forgot to mention - my preference is to use the DAC1 as preamp. When I have Marantz be the preamp the sound quantity goes south. Thanks again
A line level A/B switcher connect to Simaudio W5 input and you can select Benchmark DAC1 or Marantz AV7701 as a preamp.

http://www.goldpt.com/sw2x.html
Thank you. That does make a ton of sense. Do you know of a good one out there that has XLR connectors on both ends?