I have a problem in the mma interface - mma does not respond to keypresses until I let go of the key. For example, if I hold down the "x" key for several seconds, then mma shows nothing. Only when I let go does it show many x's.

Also, this is not just keyboard lag. If I run

(Pause[0.1];Print[#])&/@Range[50]

Then mma will not print anything till all of the 50 numbers have been submitted.

Yet if I increase the pause to 1, then mma will print each number one-by-one.

This problem makes working in mma v-e-r-y- s-l-o-w. Wolfram support cannot duplicate the problem and so cannot resolve it, although apparently one other person has reported such a problem. I am using mma 10.4 on a windows 10 computer - specifically, a Microsoft Surface Book computer.

Has anyone else found such a problem? I am wondering whether it is an issue with my computer - the Surface Books have various glitches (although I don't have any problems with any other applications on this computer). Does anyone have mma running on a Surface Book or Surface Pro 4? Or, does anyone have suggestions?

Thanks, Vilis