With a high probability that the problem is due to the inability to transfer in SysEx message the information "Note On" in hex format 0x90 - which was explained to me here:
Therefore, this data byte is accepted and interpreted by SendMIDI as EOX and then there is a fragment 64 7F F7 - which throws the remainder F7 as an undefined ambiguous message element
I began to look for a solution to a similar problem and so far I found this discussion and Wiki info
and found the mothod convert this part of sysex message
I still don't know if I'm looking in the right direction?
Setup is all right:
