Hello folks, first post on here but just wanted to share my experience with this problem.
I'm new to iCue, having only first used it a few months ago when I got a mouse & headphones which required its use. I started out using the 3.18 version & everything was fine. After a few weeks I decided to hit the 'check for updates' button & downloaded the 3.19 version. When I tried to load this version it would appear in my Task Manager & would be using a whopping 20-30% of my CPU, but the iCue wouldn't actually open, it wasn't showing in my taskbar or anything. I decided to uninstall it (thinking I'd done something wrong) and when I reinstalled it I again used the 3.18 version & it all worked fine.
I decided to wait for a few updates to pass to iron out any problems that there might have been & then just this morning went to update again, this time to 3.21... Guess what, I got the same problem! iCue would show up in my Task Manager, again using 20-30% of my CPU, but I couldn't open it & it wasn't anywhere on my taskbar. So I uninstalled again & tried the 3.20 version instead... Same problem!
Searching around the internet for a solution brought me here, and some kind fella a few pages back posted the download link to the 3.18 version I was using originally. I've downloaded & installed that & everything is working perfectly again!
I think from now on I shall live by the old "If it isn't broke, don't fix it" motto & stay on version 3.18 for quite some time!
