However it sounds, my pen that comes with Aiptek 600U suddenly became 'oversensitive' and reacts double, i.e. literally 1 click works like a double click. I checked mouse in the same settings and it works normally. I checked also 'mouse' in 'preferences', but everything seems to be normal. By the way, it happened after I reinstalled Aiptek (it stopped working after Adobe update). I'm not pro so I run out of ideas what to check. Could someone help me, please.