After about a year of great service and around 60 writes, my 2500 made it's first "Failed Burn" the other day. It appears that the surface got scratched by contact with the laser or something -- if that's possible. Here are the details:
It happened on a 4.7 GB DVD authored, rendered/compiled, then directly burned in Studio9+, using Fuji/TY -R 4x media from a batch that had always given error-free writes -- verified by Nero Speed. The stock 1.06 firmware is in place and always had allowed 8x write speeds with this 4x lot.
This time, however, the burn seemed to be taking longer than normal -- although I was distracted by work I was doing via a KVM switch on another PC at the same workstation -- so can't be sure. I switched back to the PC doing the write and saw that by the progress gauge, the burn should have been complete. But the writer's data activity light was still active.
I gave it a few more minutes to complete the burn but no progress was seemingly made -- so I aborted the burn by using the cancel button in Studio, and Studio promply crashed hard leaving an XP critical error message just before Windows crashed/rebooted on its own. But the drive activity light was off and I ejected the disc for inspection.
The burn area didn't go out as far as I thought it should have for a disc that only had three minutes of space left unused. My biggest concern, though, was the random scratches over the outer 50% of the disc, including the unwritten area. I usually inspect the surface of each disc before a burn to make sure it is free of dust, etc; I don't recall seeing anything abnormal on this disc before the burn -- but it was late, I was very tired -- so who knows? Perhaps this disc was damaged from the factory...
Fearing my drive was trashed, I tested it to see if it could still read; a pressed DVD played fine. Good!
Next, I tryed a 4.3 Gig data write to a +R disc, and that burned and read normally. Since then, I have done about 12 burns -- about 5 with discs from the same Fuji/TY -R lot that the failed burn was from -- with no problems at all. The only change I made was to limit my burn speeds to 4x, even though the FW allows 8x on these 4x discs, and I never had any problems with 8x writes before this.
So... what do you think happened? I have two theories:
1) The burn failed due to pre-existing damage on the disc; the drive is fine and did not damage the disc.
2) The disc was fine before the burn, but something corrupt in the software, the drive's hardware, or perhaps using a KVM switch during the write, caused the drive's laser (or other part) to contact the disc surface.
I had been concerned that perhaps the laser energy had somehow been over-driven and burned scratches on the surface... but that didn't sound logical. The surface is clear and non-reactive so the energy can reach the dye layer; an over-driven laser should have burned the dye layer and not the clear polycarbonate surface -- correct?
And burning a 4x disc at 8x on stock firmware, using media approved by the manufacturer and supported by the firmware's write stratagy -- won't cause the laser to damage the disc (via physical contact or high energy) -- correct?
I would be very appreciative for any feedback regarding a possible cause(s) of this strange behavior. I will not trust my drive to burn unattended until I solve this mystery. I have a scan I could submit of it if that would be helpful.
Sorry about the length of this. I did a search and couldn't find a relevant thread.