Best DAC for my situation...Read on!

Completely agree shadorne. :) The plethora of gizmos to address issues with USB transmission is a glaring example of adding band aids in an attempt to address endemic weaknesses of the technology as well as in component design/implementation, but I think there is more to digital cable influence than that.

Re: the influence of different digital cables on sound quality, as I think you have said before, this has a lot to do with the quality of the particular component’s input design and the clock implementation. Perhaps most sensitive is the component’s USB input design/implementation (vs S/PDIF or AES/EBU) as there are more potential demons to conquer with USB data transmission. Overcoming potential noise issues with USB’s unique use of the 5V power lead in the same cable/connector interface is a challenge with USB and also that most USB designs are asynchronous, thus depending on the data transmission integrity of the source and the cable to avoid data loss that impedes the DAC’s analog reconstruction process. Maybe completely jitter related as you say a lot but I am not convinced that there is not more to it than jitter. Things like impedance match/mismatch, RF/EMI rejection and signal isolation to eliminate noise riding on the signal, etc.

Anyway, very nice to agree on a balance of reasoning and listening as the superior path to better results.

Dave

The only way I would replace the Oppo 105 would be with the newest UD 205. In my opinion it is the most complete digital preamp/DAC in the market right now. You get all the usual digital connections  (usb,coax,optical) plus hdmi, and ARC (adds up as many hdmis your tv has). You also get XLRs as you know, and now Roon certified! Save the money you’d put on a more expensive DAC, get the Roon lifetime subscription with the Oppo 205 and never look back :)

Just a quick update
Received my Exogal Comet Plus on Saturday which I stole for $1000 right here on Agon in as new condition, never even been plugged in!
So obviously it still needs a lot of burn in time but initial impressions are very favourable.
Using it right now as the main preamp in the system feeding the power amp direct and I like what I hear.
Mostly listened to Tidal and my own ripped music via the Vault 2 over digital coax and very good imaging and very tight bass control. One band in particular, A Perfect Circle, has some very deep, powerful bass lines and on the old combo I could not help but feel they came over as just a tad bloated. Not with this combo, very strong and deep but crisp and well defined.
To replace the phono section on the c48, I actually bought a used Cambridge Audio Azur 551 simply because it was for sale on my local CL...lol. However cheap maybe but even vinyl sounds improved being very well defined in the lower registers and excellent on piano and acoustic guitar and vocals.

As I said, early days but it is looking good so far.

You could also try upgrading the Oppo 105 to the 205 and then sell the 105 or plug it into another system