PS3 60GB will not play Blu-Ray movies to end

[unpolire]

We have a PS3 60GB that has Sony stumped. The unit plays PS1, PS2, PS3 games, audio CDs, and DVDs flawlessly. When playing back Blu-Ray discs (brand new) the PS3 freezes after 10-12 minutes of playback and eventually gives an error message of "invalid disc" or "this disc cannot be played." Exchanging the new discs (same titles) causes the exact same result. Sony suggested the discs were the problem, because the unit plays PS3 Blu-Ray games without difficulty. I upgraded the software from version 2.17 to version 2.42 and reset all defaults, and have the exact same result. Now Sony wants me to return the PS3 to Texas for repair. Has anyone else experienced Blu-Ray playback freeze on their PS3? I searched, but this is my first post.