I'm not quite following you. In regards to the N4 you say it supports Miracast but it doesn't work with Miracast receivers? If it supports Miracast it will work with other Miracast devices. So if it doesn't work with other Miracast devices then it doesn't support Miracast. (?)
ok, let me try to explain this situation. nexus 4 totally support miracast but there is
NO Miracast COMPLIANT devices out there in the market now.
If there is a
Compliant device which you can buy now Nexus 4 will work with it.
but all the devices out there now are
PRE Compliant device. which means all those devices has half implemented(not completly implemented) miracast support and wont work properly with ANY sender devices.
Nexus 4 and and the receiver both has to support it properly to work. if the receiver(which is made by some company and not google) doesn't properly implement it how does that mean that nexus 4 doesnt support it. it means the receiver doesnt support. I hope i explained it properly.
the problem is with miracast receiver and not with nexus 4.