"DAC DUMB" needs info.

I have a friend with a Adcom GCD-700. He has been running it with the variable out so he can use the CDP remote volume.He also likes the sound the best this way and runs it through the preamp.His preamp has no remote, and he now can't live without a remote volume control.The problem is, the variable out now is shorting out and he often looses volume in one channel.We have taken it apart but there's too much in there to get to the problem area short of removing the carousel.(5 disc)The question is: is there a DAC avaliable with remote volume control? I am pushing him to keep the Adcom as he will only go with a 5 disc.The Adcom is a pretty good 5 disc transport. Im a analog man and Im clueless about DACS......thanks!!!