A data recording/reproducing apparatus comprises a data recording/reproducing component for recording data including audio and/or video data in and reproducing such data from a plurality of non-linearly accessible recording medium, a plurality of input/output processing sections for processing the input data and outputting them to the recording/reproducing component, while processing the data output from the recording/reproducing component and outputting them, a controller for controlling the input/output processing sections so as to make them carry out the processing operations in the allocated respective time slots and outputting time slot signals with a fixed cycle period to the respective input/output processing sections, the controller being so adapted that, when there is an idle input/output processing section out of the plurality of input/output processing sections, it outputs the time slot signals to be output to the idle input/output processing section to the remaining input/output processing section. With such an arrangement, more time slots are allocated to the busy input/output processing sections, which can therefore output an increased number of data sheets per unit time for a high speed data reproducing operation to improve the operability of the apparatus.