thanks for the assistance but i messed up. when i said i moved the saddles, i meant the action; up or down. the intonation seems to be ok (i got that off a site) and i've got the action sorted (moved the bridge) but the main problem seems to be the going out of tune when the bars depressed.

i've tried clamping harder, which helps but it still gets stuck slightly higher if i pull the bar up at all (which is annoying if you wanna play any vai), then drops back when i next press the bar.

standing up seems to affect it too. if i play a note and rotate the guitar at all it sorta goes up then back down again lol.