UltraBase3 DVD-RAM Drive Suddenly Stopped Working

[USSS]

I am using an x230 Tablet (Windows 7 Pro, x64) with its UltraBase3 docking station. A few days ago, the DVD-RAM drive (HL-DT-ST DVDRAM GU70N) suddenly stopped working.

Device Manager reports the drive is working properly. It will eject on demand and attempt to read a disk when inserted. However, it will not read ANY type of disk. I have tested the transport by manually moving it to its outermost position and then inserting a disk. It appears to be working fine. Firmware is up to date. Kaspersky AV found no malware on system.

I have tried uninstalling/reinstalling the device’s driver to no avail. I have also tried deleting the registry keys for Upper Filter and Lower Filter and then rebooting as suggested at several sites, including http://ccm.net/forum/affich-689426-cd-r ... -windows-7. (Deleting those keys caused a BSOD with a BCCode 7B, which required me to repair by booting back into Last Known Good Configuration.) Cleaning the lens with a cotton swab does not help, either. All socket connections between the laptop and the docking station have been cleaned with compressed air.

I have an external HP DVD drive available, but before I install it I wanted to exhaust any other troubleshooting measures. My entire system is under an extended warranty for about another year.

Any ideas? If not, would I have to send in the laptop as well to obtain warranty service on the docking station?

[RealBlackStuff]

That obviously points to a bad DVD-drive.
Contact Lenovo to replace it.
Most likely they would just send a new drive, requesting the old one back.

[USSS]

That obviously points to a bad DVD-drive.

That's what I'm thinking, RBS. Thanks.

Going to try one more potential registry fix ("Resolution 5" at https://support.microsoft.com/en-us/kb/314060). If that doesn't work, then I'll plug in the HP external drive and make Lenovo's day with a phone call.