in most cases, u are sending a general
midi instead of a sp-
midi to the 7210, which happens to suppor tonly 4poly sp-
midi. use nokia converter to convert into sp-
midi before sending.
Otherwise, if u seriously think it's the percussion, it maybe that the percussion sound map maybe too difficult for the phone to play. use psm 3.8 and above and open the
midi. check the drum settings. if it contains too many drum + cymbals, try removing some to make it simpler.
re-beam to phone and try.
good luck