While hardware may be the problem IF all CD's don't work, but if it is only the CD's you RECENTLY burned, it most likely that it isn't the hardware.
There are many reasons burned CD's do not work;
Burning a CD faster than it was suposed ex: burning a 24X CD at 30X will yeild a bad CD.
Burning a CD faster than the CD-R can burn ex: Burning at 36X on a 30X CD-R drive will yeild a bad CD.
Doing other tasks while burning CAN cause a bad CD.
If your music CD's work on your computer, if it is an OLD CD player it MAY not be able to handle 700MB / 80 Min CD's, if it can then check your burning software, in the burning section there is usually a check box to finalise the CD (or DVD) check it, because if the CD isn't finalised it won't be recognised as a music CD on CD players, some CD/DVD burning software allow you to finalize a pre recorded CD, if yours does try that, then your CD's SHOULD work.