I set the "linked" property on the hbox to make everything look like a
single widget. I'm doing this on my own to cut out the GtkAdjustment
and to just use the counter in the audio layer in its place.
Additionally, this will give me the ability to use "+" and "-" keyboard
shortcuts to activate the widgets.
Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>