Reply to Traktor Pro 2 with VCI100 freezes

Not problem in home setup.

In bar with reasonable amount of noise vci100 is placed on foam and laptop in a stand with SSD Hard drive.

Traktor locks up for aprox 7 secs whilst music still plays causing a near heart attack then springs back to life again.

This has happened twice now in same setting. Previously using the original hard drive (non ssd) which i though may have been the cause. first time i was browsing folders this time i was not touching the laptop.

Set up

2.4 core 2 duo
windows 7 32bit
4gig ram
60gig SSD drive
vci100 connected with DJranking s usb cable (not psu) latest Djranking s FW
Audio 2 dj card connected through djranking s usb cable

traktor set up. 2.0.3 using modified TP2 tsi from user on dj ranking s. though was previously using the tsi from TP1 from djranking s and TP 2.0.2
External mixer set up

anyone else experienced simular issue?