Windows spontaneously resize in remote and then in host

Hello, I'm using the most recent versions of Teamviewer on a windows 10 machine (host) and macbook air (remote). I have the windows machine set to 2560 x 1440 resolution, and I use 1920x1080 as the screen resolution setting for my Macook Air. After an hour or so of use, the teamviewer window on the macbook air suddenly collapses to a small box (about 1/6 of its normal size). I cannot drag the screen larger, and instead have to go back into resolution and change it back to 1920 x 1080. That is one of the issues I'm having.

Related to that, when I then go back to my windows machine, the windows on that machine have been resized in various ways (I'm using cubase, a music program, so it is a pain to have all the mixer windows constantly changing to strange sizes).  Any ideas what I could do to keep the resolution consistent, and to keep windows from changing sizes? Thank you!