Disklavier

As some of you know, the Yamaha Mark IV runs a version of the Linux 
operating system:

    MontaVista(R) Linux(R) Professional Edition 3.1
    Linux/i586 2.4.20_mvl31

It responds to telnet on the IP address assigned to the Piano with port 
23 and gives a login prompt.

Does anyone know usernames and passwords for the piano. I assume 
default account(s) and password(s) are created when the software is 
installed. 

In particular, I'd like to know the root password so that I can edit 
the networking configuration files such that my piano uses a static IP 
address.

Thanks