Easiest to do this one in stages.

1. Go to My TV and turn on TV. Go to a channel that is not the first in your list.
2. Go to My Radio and turn on radio.
3. Turn off radio.
4. Go back to My TV and turn on TV.
5. Expected behaviour - you turn on the channel you were previously watching.

This actually happens even though when you go back to My TV the channel/EPG information is for radio.

Now do the same but have 'automatically turn on TV' and 'Directly show fullscreen TV' enabled in config.

Now when you enter 'My TV' the second time, it will turn on TV but the channel will always be the first channel in your 'All Channels' group.

http://forum.team-mediaportal.com/mediaportal-1-1-0-rc-3-6-519/livetv-radio-livetv-tv-group-channel-has-changed-84220/