I think you mean part mute or track mute. I do this all the time, it was one of my favorite features on my X6 and it's even better on the G because you can do PART mute and not just track mute.
The difference?
One will cut notes off and bring them in instantly ( track mute ) as if you were just punching the track mute button the mixer... it can also be done with the cursor or mouse on your mixer in studio mode.
Part mute will mute the MIDI date however, not the audio signal... so notes still route through the effects and the muting sounds much more natural and to my liking.
To achieve Part Mute mode on the pads hit PAD MODE and then tap pad 8. Now all your pads are linked to the mute control of your MIDI tracks.
To do Track Mute instead hit PAD MODE and then pad 13. Once you hit pad mode you can see all your options including RPS, Samples, etc.
Also, in Part Mute try hitting the ROLL button. You'll notice 1 will blink. This means your part mute is selected on BANK 1... the first 16 tracks. Hitting pad 2 and then roll again and your pads will now mute your AUDIO tracks. I was stoked when I figured this one out. pads 3 4 and 5 continue to mute the next 16 tracks respectively.
Hope this helps!!
Also, sorry to shamelessly promote but you can see me muting audio and MIDI parts during a live recording in this video here:
http://www.youtube.com/watch?v=O7JqZ40Yhf4
Also PLEASE SUBSCRIBE I will be putting up many many more videos including tutorials in the future!