Yes, that is the correct button.
It may take several tries to flash the JBL, don't be discouraged if it doesn't take
properly the first time.
Remember to do all the resets mentioned in the instructions.
You should hold both buttons past the logo screen until the update conformation
screen appears.
If it is not updating after a number of attempts, there is still one other procedure
you can try that lets you "reset to factory settings". After that you should be
able to do the update to the current firmware. Most of the time, if you get to the
logo screen, you can do an update. So I would try that a few more times.
Luck;
Ken
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