Brian, I think it's more to do with how excited the bird is, ie, is it in response to playback - I've got a few recordings from Borneo and Peninsular Malaysia that overlap. For example, here are some from Borneo (Sabah) that are 12n/s:
XC430849 Crested Jay (Platylophus galericulatus),
XC92626 Crested Jay (Platylophus galericulatus)
and
XC29926 Crested Jay (Platylophus galericulatus). Nominate on Java also appears to overlap in call.
However, I think the machine-gun rattle is just the contact call. The true song is an odd, fluty whistle, that I transcribe as something like "pSSS see-woo" - I only hear it occasionally.
I agree with Markus, given the taxonomic affinities of the bird, Jay Shrike (or Jayshrike) makes far more sense than XXX-Jay, given it's most certainly not a jay.
James