This is probably a problem with the blank dvds you are using. Though it could simply be disks that are incompatible with your burner.
Which burner are you using? Do you have the latest firmware installed in it?
Put a blank disk in your drive, then download Nero CD/DVD Speed, http://www.cdspeed2000.com/ and look at the disk info tab. It will tell us the MID (manufacturer id code) for these disks.
This program will also tell you which firmware version you have installed. It will be next to the name of the drive.
Most of us around here recommend Verbatim 16x or Taiyo Yuden blank media. You can find TY online at sites like Rima.com and Verbatim is available locally as well as online.