How Important Is The Cdp?

Hi,

My current set-up includes PSB Stratus Mini's speakers, Cambridge AZUR 540 A and a Toshiba 3950 DVD which i use for cd playback only. I know this is a mismatch of gear, but i originally hadnly planned on using this equipment with each other, then shortly after had some money troubles so im stuck with this gear for awhile.

My system sounds OK at times, its somewhat musical but alot of the time the sound is jsut too harsh and fatuiging- guitar harmonics are especially grainy and shimmery, vocals seem to be yelling at me way too much and overall the sound seems unfocused and veiled.

My room is pretty small, about 10x10 with an open closet and Jon Risch acoustic treatments directly behind each speaker, side walls arent really treated at all. I know my room isnt the greatest, but somehow i get the sence that the room isnt the main problem im having, sure it could use alot of improvement but the bad sound seems to be coming directly from the speakers.

Im sort of confused on what is causing the harshness, some people say its my cdp, others say my amp and then theres a few who think its my speakers interacting with the room.

This brings me to the question on how important is the cdp? Ive heard many people say that the cdp makes very little to no difference and wont tame the harshness i speaker of. Others say the source is most important and that what im hearing is my speakers producing the crappy sound my cdp is feeding them.

Would a better cdp, or say a 1000$ DAC improve my system to the point where the harshness i speaker of will be mostly eliminated, or will it just show more weaknesses of my amp. Or will a better cdp just make my system only slighty less harsh by only taming some of the digital glare of cdp's?

What do you guys think? cdp causing the harshness, or is it the amp?