I am having the exact same problem (identical) and was wondering if you ever resolved this issue. Every time this occurs, I don't know if the disk I was trying to record on is still usable or not. I have a pile of unmarked disk and am not certain if any are good. I keep opening up new ones and the result is always the same. I've tried every available format that the manual says are acceptable to no avail.
Each time I load a blank disk, it goes into a lengthy "Read" process, then the display shows that the disk is ready to record and I begin recording or dubbing and it starts as if everything is working, but after about 30 seconds it stops and goes into selfcheck mode for quite a while, then the tray will open and I will get prompted to replace the disk or something like disk incompatible. This is very frustrating.
I did see something in the reference section of the user manual stating that if the unit gets turned on and off or the tray gets repeatedly opened aprox 50 times, that the record function could be disabled. However, I couldn't find instructions on how to reset the unit. Please let me know if you find a solution and I will do likewise. Thanks!