7.1 Analogue from Soundcard

[BluRayExplosion]

Tired of waiting for a decent HDMI soundcard (and one that'll work out of the box under Linux at that) I've decided to go the analogue route. I'll be outputing from the 3.5mm jacks on the sound card into the RCA jacks on my Onkyo 705. A couple potential problems struck me:

I'm planning on using Blue Jeans cable for this endeavour. Their 3.5mm to RCA cable appears to have a very large cylindrical structure behind the plug, and I'm not sure if I would be able to fit four of these as close together in proximity as the outputs on a soundcard are. Does anyone have any experience with this cable that could speak for its practicality in this situation?

Another option would be using adapters, but most of the adapters I've looked at seem to be equally massive. There are some smaller ones, but I'm really not sure about the quality. I'm not spending $200 on eight high quality analogue cables to compromise the setup due to a weak link in the chain. Any insight or help would be very much appreciated!