DX9 cassette problems... Help!

I am having problems loading the voice library sounds to my DX9 thru thge casettte. I've heard that there is a way to reset the keyboard so an error will not occurr. I have tried everything, like buying a new cassette recorder and wires, using both side of the tape etc. But to no avail. If anyone knows of a reset command that can be issued thru the front top panel please share... Thanks...