Sorry, I should have given more detail. Basically I am doing this:
SyphonImage *myFrame = [myClient newFrameImageForContext:myContext];
GLuint myTexName = [myFrame textureName];
NSSize myTexSize = [myFrame textureSize];
… etc. My code is virtually identical to that of the Simple Client.
Keep in mind that this works perfectly fine most of the time. It’s only when the Simple Server is resized that the problem occurs.
I was just thinking that maybe GL_TEXTURE_2D would be less problematic, but maybe not.