Disable profile selection while streaming

This enforces the warning that settings will not be applied until
streaming is restarted from the settings dialog for all profile settings

Also fixes a bug that would prevent start streaming/recording buttons
from being properly enabled/disabled when switching from a
recording/streaming only profile to a streaming/recording only profile
on stream stop

Additionally, the microphone volume meter got disabled when switching
from a profile with microphone enabled to a profile with microphone
disabled while the microphone was still active