Hi knia, and welcome to the forum!
Please give me some details about your chordata gear, did you solder the hardware yourself? which version are you using? How did you installed the notochord, and in which version of the Raspberry?
This is a strange error you are getting, it seems like somehow the OSC message created for output is larger than the allocated buffer. But that buffer is already large enough, and no one has yet reported an error like this with 15 sensors.
We could try changing a couple of lines in the notochord code and compiling again