Hi guys, I'm having a bit of a problem with my 21.5inch late 2012 iMac. When I turn on my iMac from standby the wireless keyboard and trackpad doesn't work for about 40 seconds after and then they light up and it works. The bizarre thing is I can wake up the iMac with the mouse and keyboard. This also only happens if its been on standby for more than a few minutes as well. If I put it on standby and wake it up straight away they will work fine. My plugged in mouse works straight away after wakeup. This problem only recently started happening. Does anyone have any suggested fix?