[ManDay]

I had this problem with the "Icarus" branded device (same hardware) before, so it appears to be a problem which is typical. The problem is that the stylus does not respond to presses in an approx. 30% of all situations with normal usage.

This is particularly annoying in the sketcher application where it becomes impossible to write normally, but it's also annoying in the normal interface because you never know whether a click got accepted.

This seems to be a software issue, though - I assume it has something to do with pressure normalization that isn't correctly handled by tslib (why does the M92 not use the famous Wacom driver, anyway?).

When this happens, it doesn't have anything to do with tilt or actual pressure. When it happens, you can move the pen all over the screen, pressing any point on the screen at any tilt to no effect. Only if you bring the tip of the stylus a bit out of proximity of the screen and then back, it re-starts functioning as if nothing had happend.