Lightroom 2015.1 is consuming at least 50% cpu all the time it's loaded and running in background (i.e. when I'm doing something else like web browsing). If I switch to make LR the active window and do something simple (in foreground) like open a menu, it drops to <10%. It's not syncing Mobile, it's not doing address lookup, it's not doing face recognition and I've left it for >24 hours to be sure it's not just doing other catalog optimising or housekeeping. Any ideas?