Please, explane "changing conversion rates"...
Do you mean changing the samplerate from inside the software or MADI card
or an actual conversion of SR's, like from 96 to 44.1 kHz?
RME features SteadyClock which can generate the wordclock from the MADI signal ( incl. refresh-anti-jitter).
Also it has the regular WC I/O (comming from the house clock or the PC card / set by the DAW)
The SR can be changed like with any other device accepting WC.
I am not to fluent with MADI, since I don't have it in studio, yet, and the MADI with my DASH 3324S is
somewhat outdated. RME is by far superior ... Read this "MIDI Theory" pages by RME... good advice, there.
RME: MADI Info Center