Okay, a few more information on my system:

Windows 7 x64
PicoScope 50000 Series PC Oscilloscope driver 2.0.3.8 used

The software was compiled with 32 bit and 64 bit, in both cases I get the precisely same behaviour (works in debug, does not so much in release)

The SDK used is r10.5.0.32

I sent in some sample code with which I reproduced the issue here.

I am using VS2012 Professional, and the .dll I am using is 1.1.0.139

I am running the PS5444B with 250 MHz, 12 bit, 2 channel, and acquire the maximum amount of values in one run. The samplecount is at 134217600 per channel. When I run my code in debug mode, everything is perfectly fine. I get everything set properly, and okay. But in Release mode only the first few ...

My code runs fine with Debug mode, or Release mode and disabled Optimization. When I turn optimization to maximize speed or Full Optimization, it hangs and doesn't do anything. I have an interface class (since it may be a different oscilloscope attached other than the PicoScope), and with each other...