I've run TS3 since it first came out. Previously it worked just fine. I stopped using it (still installed) for a little over a month. The next time I ran it, Push-To-Talk would not work at all, except in the testing mode in the options. I have tried uninstalling/reinstalling with the same results.
OS: Windows 7 Ultimate x64
Phenom 9850
4GB RAM
Logitech G500 (software installed)
Cheap keyboard (no software)
All updates for TS3 are installed
Voice activation (which does work) is not an option as my location is too noisy.