I have similar problem, but unlike Elizabeth to put the blame on Sony pre, I agree with some other suggestion on the CD player.
My Sony AV can filter "digital hash" much better than some others I have, Nakamichi 410/420, Nakamichi 730, Bryston .4, NAD 302, NAD 7155....
Your system is quite decent in my standard, and base on my experience, your problem is easily solvable.
I once swapped Sony cheapo 5 disk changer to DVP-S530, then up to DVP-7700, but the "grain" is still there, ofcourse less and less, but when I went "down" to DVP-7000, it's 70-80% clearer, finally I found a deal on 7XAES, it's 95%.
Still little grain, but bearable.
The level of grain was not changed with amp, from NAD 2200 to NAD 2600, Bryston 3B, Nak 420, Bryston 9B.
I'm not a cable believer, but I'm looking into it now.
My Sony AV can filter "digital hash" much better than some others I have, Nakamichi 410/420, Nakamichi 730, Bryston .4, NAD 302, NAD 7155....
Your system is quite decent in my standard, and base on my experience, your problem is easily solvable.
I once swapped Sony cheapo 5 disk changer to DVP-S530, then up to DVP-7700, but the "grain" is still there, ofcourse less and less, but when I went "down" to DVP-7000, it's 70-80% clearer, finally I found a deal on 7XAES, it's 95%.
Still little grain, but bearable.
The level of grain was not changed with amp, from NAD 2200 to NAD 2600, Bryston 3B, Nak 420, Bryston 9B.
I'm not a cable believer, but I'm looking into it now.