Odd problem with a Sony DVD-RW in Vaio laptop

[briven]

I have a Vaio Notebook (PCG GRT360zg) with a Sony DVD RW DW-U54A drive. I went to burn a DVD+R the other day (which the drive fully supports and which I was always able to do in the past) and the drive tried to read the blank DVD, but got nothing. I borrowed a DVD-R from a friend and it read perfectly fine. I decided to take this a step further and try out CD-Rs. The drive reads my blank CD-Rs fine, but it doesn't read all of my already burned CD-Rs. It actually does read some of them, but not all of them. Finally, I have a 2 disc recovery set from Sony that I used to reinstall my system a few months back when the hard drive had to be replaced and only the 1st disc is able to be read (luckily you only need disc 1 to install windows). I've tried restarting the computer with the CDs and DVDs in the drive and that didn't work, I've tried reinstalling the driver and that didn't work. I emailed Sony about the problem and they replied that it could be a problem with the drive itself, possibly a compatibility issue with a reinstalled hard drive (the reinstalled hard drive best buy gave me is a Toshiba MK8025GAS) and told me that if I'm still under warranty with them (which I'm not) or under warranty with a 3rd party (I'm only a year and a half into a 3 year Best Buy warranty) that I should take it in to get checked. Before I take it into Best buy I wanted to see if anyone here has any help for me. (also keep in mind that there are no firmware upgrades for this model drive so updating firmware isn't an option..doh!)

thanks