PURPOSE: To reduce uncomfortableness dependent upon tracking miss and so on, by recording information of four channel audio signals which are left side and right side signals plus the front and the back are inversed, onto information words of odd sections and even sections of the synchronizing signal respectively.

CONSTITUTION: The PCM signal is blocked roughtly by the second synchronizing signal, and further, the block is blocked in details by the first synchronizing signal 1. Information L, R, l and r of four left front, right front, left back and right back channel audio signals are recorded successively onto odd-numbered section A of the first synchronizing signal 1 determined by the second synchronizing signal, and information L and R are recorded on the 13th word and the 14th word. Next, information l and r are recorded on the 1st word and the 2nd word in even-numbered section B, and similarly, information L, R, l and r are recorded successively in order. As a result, in case that a tracking miss occurs, uncomfortableness is reduced because of only change between L and l and between R and r even for exchange between odd-numbered sections and even-numbered sections.