Maybe your baudrate is wrong?
How do you setup the clock source for the USCI? You are using 32768kHz (which is usually working, but introduces a quite large bit timing error, as 32768 doesn't divide well by 9600). If you don't use a crystal but the internal REFO, this adds some more error. And your PC side might be off too. Worst case, this all sums up on certain bit patterns to an error that leads to garbage (missed bits, framing errors etc.).