iTunes does not see iOS8 devices over wifi
I installed iOS8 on my iPhone 4S and iPad mini and now iTunes (11.4 (18)) on my iMac no longer sees these devices unless I attach them via USB. I have tried rebooting the router, the Mac and the devices. I have reinstalled iTunes. I have checked that the appropriate settings for wifi sync are correctly set on all machines. Any suggestions?
iMac (21.5-inch Mid 2010), OS X Mavericks (10.9.2)