I seem to have fixed this problem, or at least found a work around. I noticed in the control settings Mouse+Keyboard was enabled as the input devices. Since I never use the mouse I have changed this to Keyboard only. This seems to have fixed the problem. Not sure if I had Mouse+Keyboard enabled before this bug developed or whether it defaulted to the Mouse+Keyboard setting at some point and this caused the problem. But at least things are working as expected now.

Suddenly started getting a bug today when playing Juggernaut where every time I become the Jugg the turret is frozen, the turret controls either don't work or partially work, but the turret kind of stays pointing in one direction. I also get the problem if I change turrets. If I reset the game the problem disappears, But of course if I'm the Jugg it means losing the Jugg so this makes the game unplayable. I've checked my keyboard connections and even tried to reset the keyboard using the N key. However it doesn't seem to be an error with my keyboard because it only happens when I become the Jugg or change equipment. I've also updated the game client. However I'm still getting the problem so it definitely seems to be a bug in the game.

I've since discovered the keys can be reassigned in settings. They now default to 1,2,3...etc rather than num1, num2 ,num3...etc. That seems to be what caused the problem with the number pad, but it's easy to reassign the keys by selecting each supply icon on the control page and pressing the appropriate key on the number pad.

The number pad is also not working to activate supplies for me too. I have a CM Storm Quickfire Pro I've tried all the usual things which might cause this. Also tried a different browser but was unable to solve the problem. So it does seem to be a bug in the game (the HTML5 version). At least I hope it's a bug, and not something done by intention because having to use the numbers at the top instead is far from ideal given the speed of play.