Does ProTee VX interfere with other infrared devices?

Yes, The ProTee VX and devices like the GC2, GC3 or above both use their own infrared lights to track your swing and ball. When both are running at the same time, their lights can mix together and mess things up, causing interference.

To use both simultaneously, you’d need to block the light from one device completely, but then that device wouldn’t work, so they can’t be used together.