Audio sounds robotic or choppy. Fix: Go to Sound Settings → Device Properties → Additional Device Properties → Advanced. Change the default format to 24-bit, 48000 Hz.
However, I can tell you how to get the legitimate PC version: halo reach full game download for pc
If your PC was built in the last 5 to 7 years, you will likely be able to run the campaign at a solid 60 FPS with mid-to-high settings. Audio sounds robotic or choppy