Artifacts when HDMI is connected

[MacMillan]

Hello friends!
I am engaged in video shooting, I use Canon 5D Mark II and monitor Viltrox DC-70 II via HDMI. Recently, I began to experience problems with recording video in the format MLV. The video began to appear pink random artifacts, as well as a shift of the lower part of the frame. At first I thought it was a firmware problem and tried to try older firmware, but this did not solve the problem. I tried to change a lot of settings, but it turned out that the problem is in the HDMI connection. If you turn off HDMI video recording in MLV is perfect, without artifacts and strips. I also tried the AV output and the recording is obtained without artifacts. Who faced such problems?