PSR-S970/PSR-S770 Owners Manual
Page 116
.... Contact your authorized Yamaha dealer or Yamaha Customer Service if you to be accompanied by a detailed explanation of the problem(s) requiring service, together with the original or a machine reproduction of the bill of sale or other rights which the serial number has been defaced, modified or removed...; (c) normal wear and any other external causes such as evidence of warranty coverage. Yamaha may also have any questions about service received or ...
.... Contact your authorized Yamaha dealer or Yamaha Customer Service if you to be accompanied by a detailed explanation of the problem(s) requiring service, together with the original or a machine reproduction of the bill of sale or other rights which the serial number has been defaced, modified or removed...; (c) normal wear and any other external causes such as evidence of warranty coverage. Yamaha may also have any questions about service received or ...