The fact that it seems to "come and go" makes me want to tell you to just get a new battery.
Other than that, be sure the battery terminals are clean, clean, CLEAN!


The sensor in the top and the one for the divider would not cause this.
The sensor in the windshield frame would cause this, and the light in the top switch would light as well.
Is the light in the switch lit at the times that the beeping occurs?

I don't think it's the one-touch module.