Magic mouse interferes with WIFI connection in Yosemite 10.10.3

The magic mouse still interferes with WIFI connection in Yosemite 10.10.3. When the magic mouse is connected with the computer through the bluetooth, the wifi speed will reduce to zero in a few minute. And if the magic mouse is disconnected, the wifi speed recovers almost immediately.

This problem can be temporarily corrected by switching between the different wifi bandwidths in the router's settings page. However, if the bluetooth is connected at the start-up of the computer, this problem reappears.

Is there anyone who can help me out here? Thank you.