Problems with BDROM LG CH08LS10

Ive been looking over this site for Media Center info for a while, and thought maybe someone might have some input on my problem.

I built myself my first HTPC recently and spent a lot of time configuring it with Windows Vista Ultimate, a tv tuner and onboard HDMI video/audio output to my a/v receiver.

I have found that MANY blu-ray discs are not being read by my BDROM, the model is LG CH08LS10. I have tried roughly 20 in total, some rented, purchased, and some borrowed from a friend. When they work it's fantastic, but I find it extremely frustrating that so many disks are not working. I have upgraded the firmware from LG's website and it made no difference. I am using the latest build of PowerDVD 9 Ultra to play the blurays. In case it matters, here are some of the discs I can think of that are not working. Most of them will read and start running, but get stuck at some point while watching and won't go any further:

Sunrise
Short Circuit
The Princess Bride
The Ultimate Avengers Collection
Robocop (windows does not even detect this disc is inserted)
The Fountain (windows also does not detect this inserted)

The fact that it reads part of the movie makes it sound like the disc is bad, but I have a hard time believing I have such horrible luck to be finding around 10 bad discs out of 20 I've tried, what are the odds of that from different sources??

Ones that have worked fine for me:
300
Apocalypto
Star Trek 2 wrath of khan
Appleseed Ex Machina
Year One
X-Men Origins Wolverine

I'd appreciate your input. unfortunately it took a bit of time to find out this was such a serious problem so I can't return the drive for a refund to the store where I bought it, and am considering doing an RMA with LG at this point. These problems are not erratic, they are consistent when tested days apart with the same discs.

Tell us what your video card is and your monitor also.

You might want to upgrade to a video card, like the 4670.
It might solve the lag.
Try replacing the TV with a HDCP compatilbe monitor temporarily if you have one.

I will be upgrading to an ATI 5xxx series card for bitstreaming HD audio once one is released that's fairly affordable and does not require a 2 slot installation (why do ALL of the initial releases require 2 slots??). I am not sure what you mean by "lag" though, this pc very easily handles bluray playback when the discs are actually working.

I will run the pc bluray test as well, though I doubt this will find anything wrong since half the blurays I have tried work fine so obviously the system is capable of playing blurays.

Swapping in a monitor is not very practical for testing for me since the htpc is in my living room, and wired into my A/V receiver, then to the TV. I'm not sure what you are looking for me to test with that though, that the TV could be causing the bluray to stop playing after 44% of the movie is done? (not all movies stop after 44%, but the copy of princess bride I borrowed did for example). I also don't see how the TV could be involved in those discs that are not recognized as being inserted at all.

Just for reference, I had initially loaded windows 7 and it detected my actual brand and model of plasma TV as an HDCP compliant device. I had to load Vista unfortunately due to driver problems with my tv tuner.