Yamaha DME24N Processor Firmware 4.05 Mar 24, 2016
... or earlier. (This does not apply to the SP2060 or ICP1.) If you need to upgrade your DME from V3.5x or earlier to V3.81 or later (including V4.0), please contact your Yamaha dealer. - It is needless to change the DME hardware when you need to upgrade/downgrade between V3.8x and ...