Can't get to grips with this. I can't seem to get the right sound, its hard to explain. Its like a clicky sound rather than a chunch sound, anyway it just don't sound right. Any suggestions ?
You should be muting (which, btw, isn't quite the right word) the strings close to the bridge, in case you're not already doing that.
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Its like a clicky sound rather than a chunch sound

Try applying less pressure to the strings, or moving your muting hand closer to the bridge. Just experiment with pressure and position.

Also, your tone may be bad for muting? Try messing around with the gain, more gain makes things easier for the most part. =P