When waking up my MacBook Pro, the external monitor unpredictably displays “snow flak

[singjai]

I can't seem to pinpoint a specific cause for this, but sometimes when I wake my MBP the external screen gets fuzzy, like a TV with no reception. If I sleep the display again (with hot corners) and wake it up again it's fine. Anyone know how to fix this?

This is a repost from another forum and the same thing is happening to me. It seems to only do this with Acer monitors as my Samsung worked fine? Does anyone know a fix to prevent this from happening other than replugging the HDMI from my mac?

 

[jorgk]

... the external screen gets fuzzy, like a TV with no reception. ...

I got the same picture when the connection between the Display-port/Thunderbolt-port and the external-display adapter sometimes lost contact. Just plugging in and out at the MBP would (mostly) restore the connection. Trying to move the plug on the MBP sometimes recapitulated the effect.

Appeared after a LB exchange, disappeared after the next LB exchange.