A video tape recorder includes a rotary cylinder of double-azimuth four-head structure having a pair of main heads and a pair of subheads. When it is detected base on an envelop signal that clogging or the like occurs in the pair of main heads, a controller performs a head change so as to record a video signal by using the pair of subheads, and changes a phase of a control signal that is to be recorded on a magnetic tape by 180 degrees.