After a while, the trackpad or mouse requires me to click twice to be able to register a single click
After some testing, I realized that this only seems to happen after I have opened the application "mumble" (a VOIP app). There's also a discussion about it on the sourceforge forums. Here's a link to the sourceforge discussion about this same issue: http://sourceforge.net/projects/mumble/forums/forum/492607/topic/4886530/index/page/1