Nabarunpaul,

  Have you tested both the XLR and 1/4" Outputs of the POD X3 Live?  have you tried using the ground lift switch to see if that makes a difference?  Have you made sure that the POD, computer, and PA are all being powered from the same power source?

  You should test this in different locations just to be sure if it is a problem with the hardware or just an issue with the power in that location.

  Regards,

  Line6Hugo