I just updated my bdp1500 and have the same problems. According to the customer rep I talked to, it may be a full memory problem. He wasn't able to help me because I don't have BD Live. If you find out a solution let me know.
I did an online upgrade of the firmware on my 2500 and now it cannot read blu ray discs. It still plays standard DVDs and Netflix, but it says it can't read any blu ray disc I put in. I reset the unit by holding down the FF button in the hopes that it would reset the firmware back to the original, but no luck.
Any help is appreciated.