No as I see it. I haven’t had that line and I had no problems with it while using sys-audio for non-microphone use. Tried something in order to use microphone and sys-audio stopped working at all, only to discover that now I need this line out of the blue to get sys-audio back. 
In addition I got 2 new (weird?) errors not seen before, but I am not sure how specific they are for my configuration
admin.vm.device.mic.Available * sys-audio * allow target=dom0
admin.vm.device.usb.Available * sys-audio sys-usb(net) allow target=dom0
Still not working microphone with integrated web camera… Any help appreciated…