Can I use a component video switch to switch RCA audio channels instead of video?

I have a 7.1-channel surround-sound amplifier (Denon 1910). It only has one set of 8 RCA inputs for analog audio. Unfortunately, I need two sets. I found a switch box for RCA component video which looks promising.

http://www.amazon.com/Audio-Composite-Selector-Swi...

Since component video is based on RCA cables, and these are un-powered switch boxes, I would assume that there is no processing of the signal in the switch box and that there is theoretically no difference between switching component video cables with these boxes and component audio cables.

If this seems feasible, my intention is to purchase three of these and hook them up to my 8-channel analog input. I would then have the capacity to attach a total of three sets of 7.1 surround analog cables to my receiver. Granted, I would have to go through the inconvenience of flipping three switches every time I wanted to change the source, but at least I would have a way of adding more surround to my system. Other solutions I have found like converting the analog inputs to HDMI are ludicrously expensive.

In case you're wondering how I ended up in this quandary, my computer is hooked up to the analog jacks. My sound card is 7.1 but only through the analog outputs which sound a heck of a lot better than the digital SPDIF out which is limited to 6.1 surround. The second set is needed because for some unfathomable reason my "universal" DVD player (Denon 1920) only allows transmission of SACD audio through analog output. I have the SACD feature working in stereo, but I want surround.

Is there any reason I couldn't use switch marketed for component video to switch RCA audio instead?