I've had a ton of experience with electronic audio equipment over the years.  I worked for years selling HT products so I have an understanding of discrete surround sound and the associated hardware.   I'm new to PC gaming and am somewhat confused by multi channel audio and how it's...

All things being equal is there a mechanical/audible difference between the two sizes of headphone jack?  Does contact surface area come into play?

Anyone using an Uninterrupted Power Supply with their PC based audio system?  Is it audible when powering your system?