Windows 7 burning madness

[toastmaster]

i once burned at 8x or 16x with no errors,even and clean burn.but now all of a sudden 4x is highest without "rings of saturn" and unplayable discs.Help! W7/64 laptop/facory optiarc/LG external.(all burning programs tried)

 

[Josephur]

Did you recently change brands of blank media your using, are you using the same exact blank medias?

 

[toastmaster]

No difference in discs,so I wonder if some sort of data transfer problem,since my rocketstick has slowed to 20 kb/s at best.My ext. drive and usb devices are very fast though.Does anyone know of a diagnoistic/test program for DVD-ROM drives?