Emu XL-7 & MP-7 User's Group

This is not the original poster's problem.

Note that the SYSEX PACKET DELAY parameter is NOT applicable to OS
updates (nor to Sequence transfers when using E-Loader). That
parameter is only used in open-loop (non-handshaked) transfers. OS
updates are done closed-loop (handshaked) and do not require fixed
delay times between packets in data transfers. Closed-loop transfers
occur at the maximum speed that the unit can accept MIDI and use
check-summed packets and support retries in cases of
dropped/corrupted packets.

YEAR !! but i have had the same problem when i tried to update to new OS
... and when i set the sysex delay on 300 ms, that's solved my problem !!
and i wasn't the only one with this problem ...a friend advice me to do
this and it's works fine !