Default (H) Screen mirroring problem.

Hi,
I have a problem using screen mirroring and videos from internet (youtube, etc..).
If i turn off screen mirroring, videos play fine on the tablet. When i want to play the same video with screen mirroring, it is very slow and it fails after few seconds (on the tv and on the tablet).
If i use the tablet with content in the internal memory (such as videos, games, etc...), it's play fine on the tv. But when i try to see some network content (videos from internet, from a network storage, etc...) it fails.
It is as if screen mirroring takes all the bandwith of the wifi network and the other datas can't go trought it.

It's a serious limitation of the functionnality if it is normal.

The screen mirroring function of my galaxy s4 let me see videos from internet or from my network storage without any problem (in the same environnement).

Is there a solution to do it with Z2 tablet ?