Imac burning cd's issue

I have an imac 21.5 which is just a couple of months old. It won't burn CD's, I use Sony cd-r and it starts to burn then stops after a few seconds with an error code. It also doesn't seem to like reading CD's either, sometimes it does sometimes it doesn't. We have two of these machines in our office and the other one is doing similar things. Has anyone else had probs with these newer machines?
Thanks.

Welcome to the Mac Forums.

Since the same thing is happening on two machines, it could be the quality of the media. Try using another brand of CD disks. I know from experience that office suppliers (purchasers) tend to lean toward buying the least expensive of consumables.

If upon trying other brands the same is happening, have the machines looked at. They should still be under warranty.

Test the iMacs with a commercially-produced cd and dvd, be it music, movie, whatever. If the fault persists, I'd suggest you have faulty optical drives, and, as suggested, have them checked under existing warranty.

There are several threads in Mac-Forums on recommended (alternative) brands of optical media.

Thanks for the advice, will give these things a try.