Q: “Will the MOTU 828mkII pass subcode information like track IDs through the S/PDIF port?”
A: Track IDs, CD Text and other subcode info are stored in unused bits that are part of the digital data stream that makes up a S/PDIF signal. If you send a S/PDIF signal through any MOTU interface, the subcode info will be included. Be sure not to change the level of the S/PDIF signal, as this will alter the bits and the subcode data may be lost.
Using the 828mkII this way gives you some extra conversion options. If, for example, you have a CD player with only optical S/PDIF out that you wish to transfer to a DAT machine with only Coax S/PDIF in, you can send the optical signal into your 828 and route it out via Coax with the subcode intact.