It was me ...
Ok ...
You ready ?
The way an MPC3000 boots and allocates it's internal work space memory via the CPU memory control registers when booting a *.SYS file and running the OS loaded from floppy is quite different and far from optimized when compared with loading from ROM. ( This is nothing to do with wave/sample memory )
IE: The machines internal memory mapping layout operates in a way that is not as high-performing when compared with how the OS initialises when it is run from ROM.
In simple, this and the reduced available SEQ memory when booting from floppy disk are pretty solid reasons why "FLOPPY-BOOT-DISKS" are only ever one shot use devices.
You'll minimise the potential for MANY different types of "OS errors" that can happen on a machine.
Highly recommended to make certain an MPC3000 is loaded with it's OS in ROM.
You dig ?
Rohan.