If I connect a phone to a TV, with a HDMI cable and a MHL adapter, then there are artifacts displayed on the TV screen, repeatedly. They last for a few seconds, then they disappear.

If I disconnect the HDMI cable from the MHL adapter, and connect it to the HDMI port of a laptop, these artifacts and interruptions never occur.

If I disconnect the HDMI cable from the MHL adapter, and connect it to a external DVB-C receiver, these artifacts and interruptions never occur.

So the problem seems to be either in the MHL adapter, or the phone. What could be the cause, and is there a fix for this?