Installed a KX-TD7896B cordless to a KX-TA624. When a call presents the cordless will vibrate. I went into the cordless settings and set incoming to vibrate > ring. That did not work. Turned vibrate off and set the speaker volume to 6. That did not work. It always vibrates. When I plug the cordless into a corded jack then the cordless does ring. The only ring selection for extension I can find is for internal intercom calls (115). There must be a setting that controls this.