Here is an interesting bug (or chain of multiple bugs). It's hard to describe them by words, so just follow these steps (I assume that you have vertical sliders and labels shown in kmix, and the kmix tray icon is at the right-most position on your panel, so if you have a clock there, just (re)move it temporarily): 1- Left click on kmix icon in the system tray. Click on Mixer. 2- Settings -> Configure Kmix -> Uncheck "Show Labels" -> Click OK At this point you should see the first bug: The window size doesn't shrink to the total width of the sliders, leaving a useless space on the right-hand side of the kmix window. 3- Enlarge the kmix window downwards, so the sliders are longer. 4- Click on the close button on top-right of the kmix window. It will dock into the tray 5- Left click on kmix icon in the system tray. Second bug: The menu that contains the main slider(s) and the Mixer button is off-screen. 6- But you can still click the Mixer button, which is halfway off-screen. Click on the Mixer button. Third bug (?): The window size is not remembered. I'm not sure if it is supposed to though. 7- Settings -> Configure Kmix -> Check "Show Labels" -> Click OK Fourth bug: Now, only some of the slider labels show up. This seems to me random. Sometimes certain labels show up, other times different ones do. To get all the slider labels show up, you will need to manually enlarge the window horizontally. If you dock kmix to tray and reopen it, those labels will still be missing. I don't remember having these issues prior to Qt4.5. But I may be wrong. Orcan