Frame rate: exporting an animation to Harmonic ChannelPort eventually executes in "double time"

Hello there, noobie's question:

Sometimes, I have to publish animations for execution on a Harmonic ChannelPort professional graphics system, within a broadcast facility. The entire plant works under 30fps and the equipment is set accordingly, but the graphics themselves must be published set as 60fps animations; otherwise it plays in apparent double speed.

Any clue, theory or case where the same behaviour is noticed?

Thanks in advance.