Switching from ReadyNAS Duo V1 to V2: New Version of ReadyDLNA shows but does not play media files on UPnP-Client (Error: "Format not supported"). Does ReadyDLNA have transcoding functionality built in ???
Update: I downgraded the firmware to Version 5.3.3 !
All media files can now be played on the UPnP client (Philips streamium SL300i)
What went bad from Version 5.3.3 to 5.3.5 ?
Not sure about specifics with ReadyNAS version numbering, but it sounds like the media formats that you are using have had their DLNA_PN types changed between the two versions from a type that works with your Streamium, to one that doesn't
DLNA is so weakly specified, and certification performed against such a small set of media types (MP3, WAV, JPG and MPEG2 IIRC) that most client implementations for newer file types are different, and the server authors run in circles trying to match formats against clients.