I tried setting the "header bytes" to 0 and starting the complete frame at the packet bytes.
Now at least it do not corrupt any audio but no SPD frame is said to be received.
Packet memory starting from 0x00
0 0 0 3 1 25 70 70 70 70 80 80 80 80 71 71 71 71 81 81 81 81 71 71 71 71 81 81 81 81 5
I have also tried all kind of sequences of the SPD Packet Update bit. But no success.
Martin