Moving this discussion to the Premiere Pro CS5, CS5.5, & CS6 forum.
Did you lose sound on existing mts files on timeline or is it lost on fresh import of mts files.
What's your operating system
It was on the fresh imported ones. I have Windows 8 64 bit.
I just now did a complete reinstall of Premiere Pro and started from scratch and now it works again.
Thanks for the update Kristian.