Need help, again, for Sony Q28A Burned +-R blank again

Really I’m pissed off with this drive, lately it started with power calibration error.
I thought that it was error witihin Nero 7, but I’ve uninstaled Nero 7, cleaned registry for traces of the same, installed Nero 7 again, started burning and it finished normaly but when I’ve reinserted media but it was blank. I could easily burn that media again. When I’ve burned that same media again it was blank again ( about 4 times ).

Burner Sony Q28A OEM
Burning software: Nero7
Media used: Verbatim -R 8x
Firmware: KYS4

Please help.

Ok now I tried using eeprom reset media learn, done Smartburn option, and now I’ve burned that same, over and over blank, DVD perfectly. I don’t know is this a firmware problem or what. Is there any chance of disabling media learning on Q28A?

Is it possible that the “simulation” check box has been checked in Nero?

No. Other help?

Maybe the laser is too weak for burning. Test the drive in another PC before replacing it.