Midi editor cutting off note trails

[gamwtonxristo]

hi guys ,at first i though there was a problem only with superior drummer,but then i realize that i have the same problem with all vsts ,well the problem is that when i load vst to an instrument track ,althought in playback everything is fine,when i go to midi editor to draw some notes the sound is getting cutted,i ve tried many things such as changing rtas proccessors or the buffer cache but nothing changed at all,

please guys i really need some help because its matter of buissness,

my gear is
( pro tools le 8 with a digi 003 in 4core pc with 4 gig ram and window xp 32)

[gamwtonxristo]

hey guys unfortunately i dont see any respond,

well somehow i found that enabling dynamic transport make things better,but i think that the problem hasn't to do with that,too confused,tired