Access violation occurs when calling from C++/CLI

[developmentalmadness]

I've posted the following on StackOverflow and because I'm not sure I'm actually passing in the right values as parameters I am cross posting here (apologies). http://stackoverflow.com/questions/10249237/c-cli-noob-system-accessviolationexception

The entire source for what I'm trying to do is here: https://github.com/developmentalmadness/echoprint-net/tree/3c48d3783136188bfa213d3e9fd1ebea0f151bed

I'm assuming the samples parameter in the Codegen ctor is the number of elements in the buffer. Also, the buffer's source is actually an array of bytes not floats. It's the raw data coming from the microphone and I'm just converting it from an array of bytes to floats.