The PAUSEUS statement has a minimum time it can delay.
It has to calculate what to do each use at Run-Time.

@  4Mhz, the delay is 24us

A "1us minimum" delay routine can be found here ...
http://www.picbasic.co.uk/forum/showthread.php?p=22098

Another possibility is corruption of the Pause command from using a Bootloader without ...
DEFINE LOADER_USED 1
( but, nobody ever admits to that one. )
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