Preview in imaq hangs from second time

Hii, I am trying patiently to code a custom adaptor. Additionaly I added three pointers(std::string) to the demo adaptor class.

My problem is during the first preview i am able to work everything good. Once i do a imaqreset and videoinput again, the next preview hangs up before even calling the start capture method.There is an unresponsive black screen.If i ditch the three pointers it would work..but i need em:)

Has anyone got any hints or advice..Im stuck with this issue for a while..

Denny