How come i hear background noise on lame mp3 files ripped with dbpoweramp?

We will need more information than that. Lossy encoding inherently adds noise, but if there are sufficient bits to do the encode then the added noise should not be audible.

Exactly what settings are you using, and are your rips accurate?

i am using lame mp3 320kbps cbr with slow encodeing and acurate rip says my rips are acurate.

Is the noise only present when you play the files on your computer, or is it present no matter how they are played?

i can hear the noise on my computer and on my dap, it is a sansa e260 version 1

I think i can also hear it on the cd player when i play the cd in the cd player.

So i am guessing it is the cd.

the cd is U2-October

The song was October