The Sony 510 is probably the last good drive Sony (not a lite-on) put out. His case sounds like a simple poor quality media problem to me.
Victor try some good quality media and update the firmware to the latest from Sony before giving up on that drive, if you don't want to buy a new drive just because you want one. Be sure to follow Sony's instructions on flashing firmware for that drive. I have burnt over 200 DVDs with that model drive and as long as I use good media I don't get any pixelation or freeze frames with it.
If you want a new drive I don't think you could go wrong with a Benq. :bigsmile: