Retooling hardware is a lot more expensive than modifying software. So, why not design the firmware in the slotMusic player so that at startup it looks for a certain named file in the microSD card. The file could contain wanted options like RANDOM=YES/NO and LOOP=YES/NO. If it had these capabilities I’d buy one for my mom. What other simple options might be useful? To change the options you’d have to edit and save the file back to the card. Things not recognized would be ignored. If the file was not found it would use the defaults.
Just a thought.