Metro Outputs without OMS or MSS If you are not using OMS or MSS, Metro creates an initial 32 Metro Outputs16 for the Printer port, 16 for the Modem port. The number of Outputs you can view simultaneously depends on the size of your Macintosh screen. Selecting Import Audio File from the File menu automatically creates a new Output which is assigned to an audio port. Up to 64 Output channels can be assigned to a single audio port. You can build on the initial 32 Outputs, creating up to 254 Outputs, by copying existing Outputs or using the Modify Outputs and Busses dialog box within the Special menu to assign new Outputs to different MIDI ports and channels and audio ports. You can also delete Outputs if you choose to work with fewer than 32; for example, you may want the same number of Outputs as device channels you’re working with.