ok, that wont clean it correctly Sam.
you will need to use an actual lens cleaner, one you can get herehttp://www.amazon.co.uk/Hama-CD-DVD-Lens-Cleaner/dp/B000S5UJRQ
You then run the cleaning disk.
Once done, test your own disks again. If it still fails then it confirms the problem.
It will be the Lens unit itself that will have faulted. We have ruled out all other causes.
In this case, you are going to have to return the recorder to have this replaced. It will be covered by the warranty if this has not expired, and the replacement will be done at no cost to you. If the warranty has expired, a repair will generally cost more then the value or a replacement unit, when taking into account the limited warranty you would receive.
If you would like any additional information or assistance, please do not hesitate to let me know.
And if you can take a second to rate my service, that would be greatly appreciated.