Hey @amritz.fa, just to confirm: the TIR works with the multiplexer, but when you place it directly on the EV3, it does not work. Is that correct?
This should be possible to program in Labview, but we don't have the supporting code. We have not been allowed to be part of the Labview developer program, and haven't supported that code. However, it should be possible if you setup some basic I2C calls. I'm unfamiliar with Labview for EV3, but I'm going to assume it has some I2C blocks that can be used to make direct calls to sensors, is that right?