Cubase Giga Studio Problem!!HELP!!

[dolikethis]

Hi people out there..

im just starting with Giga studio...
and dont know absolute nothing what to do..

If i set nemesys giga Ports (Cubase Setup MME) to active
the vst instruments get distorted
(like Latency Problem)
But if the ports are inactive...everything is ok...

does anybody know what i can do to solve this problem...???

im using RME hammerfall and SB live..
and im actually quite sure that it is not
a irq problem...or..acpi..thing..

im using cubase 5.1 and...Giga 160 v.250

Can anybody please help me???

p.s sorry for my bad english...