1. An in-vehicle device comprising: a radio tuner configured to receive a radiofrequency wave and playback a content of the received radiofrequency wave; a television tuner configured to receive a television frequency wave and playback a content of the received television frequency wave; a playback control unit configured to control playback of an image and a sound stored in a storage medium; a first system including: a first audio output unit configured to output a sound according to an audio signal generated by the radio tuner, the television tuner, and the playback control unit; and a first indication unit configured to indicate an image according to image data generated by the television tuner and the playback control unit; a map data storage unit configured to store map data as a source of a map image indicated by the indication unit; a navigation unit configured to detect a present position and superimpose the detected present position on a map indicated by the indication unit; a route search unit configured to search for a route in accordance with a predetermined procedure and superimpose the searched route on the map indicated by the indication unit; a processing unit configured to: control the radio tuner, the television tuner, the playback control unit, the indication unit, the navigation unit, and the route search unit; and execute at least one of a task of the radio tuner, a task of the television tuner, a task of the playback control unit, a task of the indication unit, a task of the navigation unit, and a task of the route search unit, in accordance with a first predetermined priority; and a processing suspension unit configured to suspend one or more selected tasks from among a plurality of current tasks currently being executed by the processing unit, irrespective of the priority of the one or more selected tasks in accordance with the first predetermined priority, when the processing unit needs to execute a new task, such that execution of the plurality of current tasks plus the new task by the processing unit would exceed a processing performance of the processing unit, wherein the processing suspension unit suspends the one or more selected tasks from among the plurality of current tasks currently being executed by the processing unit in accordance with a second predetermined priority that is different from the first predetermined priority.