yes i have the same problem like you... Tested on stock poland kitkat, and some roms based on it. If i plug in the hdmi cable touchwizz loucher feels laggy, movies are not working well. When i disconect all is fine. My android mediaplayer(4400 points antutu) playes movies in full hd over lan fluently.... Note3(sm-9005) not.
Sorry for my englisch.... I cam from germany.
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