cd players with volume control

High voltage outs are what you are looking for....

check the archives. You'll find numerous answers there.

Look for a vintage Denon DCD-3520 CD player. You'll be amazed with this player either fixed with preamp or variable volume out.

Wadia....
Benchmark Dac (if you want to go separate)
Some Theta models (Miles?)
Some Shangling models.
Resolution Audio models.
Audio Aero Capitole.

Make it sure that your amp has high input impedance.

These must have analogue volume control:
Resolution Audio Opus 21
Levinson No. 39, 390S
Audio Aero Capitole, Prima, Granite 657
Theta Miles
Cary 308T, 303/300
Digital volume must bee in most Wadia, Marantz and Accuphase players also Gamut, Shanling SCD-T 200/100, Consonance Droplet and many others. You can find a many topics about this here in forums too.
http://forum.audiogon.com/cgi-bin/fr.pl?ddgtl&1127503682&read&keyw&zzvolume
Good luck!