I own the EM-101 Soundplus by Roland serial number 624315 that is attached to my Roland HP-5600 digital piano by way of MIDI to create added sounds. The problerm is that when plugged in it turns on but no sound is created. This occurred back in 1995 and haven't used it since. I have tried to solve the problem but to no avail. Could it be the plug in multi pin jack cords? internal failure? I would like to solve its problem so I can go back to enjoying the sounds I used to have. Can anyone lend some advice to this problem, it works but it doesn't?