Musical Fidelity A324 DAC with Marantz SA8260

would suggest simple tweeking of your 8260 before adding a dac...(this is pretty much true of most digital gear)

i had a 8260 for a couple of years and the unit sonics really improve with a decent power cord (i like the audience), bdr cones and pucks, seismic sink, bright star audio sand box, and a vpi brick....

though the tweeks are $$$$$, they can be used with any cd player.

I had this combination some time ago and heard little difference between the redbook performance of the SA8260 and coursing the digital output through the MFA324. If anything, the redbook performance of the Marantz seemed to have a little more presence. Sold the MF A324 soon thereafter. I still have the SA8260 although it frequently hangs when reading hybrid SACDs ( grrrr!)

I once combined an ARC CD-1 with this same MF DAC and it was a huge improvement over the Levinson 36 DAC it replaced, at least when combined with the ARC player. I've had Wadia and Shanling since, so I've not used an outboard DAC. I was happy with the MF at that time, though. I think I'd give that 8260 a strong listen before adding another DAC