"Connection Error" while downloading patches

Since the 3.21.2 patch I'm frequently getting "Connection Error" messages during patch downloads and I have to restart the client to continue.

I have also noticed that it often drops huge chunks of data, 40, 50, sometimes up to 100 MB... it's jumping back and trying again multiple times. I have never seen it doing this before. Turns downloading those big patches into a nightmare with my rather slow connection. Anyone else having such issues?