Thanks for the vote of confidence everybody. I may really not be nuts.
Now the only question is will I be able to notice any (listening) difference between the Squeezebox Duet (DAC) currently being used and a Behringer UCA202 DAC currently hooked up to the computer.
My guess is I will not be able to tell the difference. Speakers are a pair of Ascend Sierra-1s.
This speaker wire idea came about because I bought the Behringer to upgrade my computer sound. The Behringer currently feeds an old Marantz SR1000 into a couple Polk R15 bookshelf speakers. The SR1000 looks nice but sonic wise it's seen better days.
Cat5 cable is 24-26AWG, probably not the best choice. I'd use 14AWG speaker wire.
I haven't got any experience with the Duet but have used both Squeezebox original and Touch, no problems with their DAC that my amateur ears could pick up. My configuration now uses DAC in my receivers instead but only due to convenience.