From a support standpoint, I can tell you that, currently, the ConnectPort Display M22 does not have audio support enabled, and USB printers are not supported. The kinds of USB devices that are supported are mice, keyboards, and most HID-style input devices, i.e. barcode scanners.
I'll have a sales rep contact you to let you know the ETA for audio support, and to discuss possible printer support in further detail, as it relates to your application.
Apologies for any inconvenience.