But i am having this dilemma. I check the I/O to do a bit of studying.
This will most likely be the configuration that I will use.

PC(X-fi Titanium) ----> S550 via 5.1 input
PS3 ----> S550 via AUX input

would this affects the the sounds quality of either one?
is there a hub out there that will solve this issue.
I may be able to connect the PC and PS3 to the TV and reroute it to the S550
but not sure if that's possible

too bad S550 does not come with an optical input otherwise it will be a straight forward thing