What you have been told is not true. You should be entitled to a full refund under the Sale Of Goods Act - the product has not lasted a reasonable lenght of time.
Is it not under warranty anyway?
Your best course of action is to write to Dabs and send it by special delivery (you can then prove they got the letter) and say that you wish to reject the CDRW as not suitable for the purpose that it was sold for and has not lasted a reasonable lenght of time.
State that you would like them to collect the device within X days (no more than 14) and that you would like a full refund.
There is little point in getting a repair on a device like this.
What make is it? You may in some cases get a better response out of the makers, but you have a contract with Dabs and with no-one else.