Well i get the lack of buffering may be a problem, but i had new issues when i put the buffer chips so now i am trying to figure out what is causing the problem because it looks like there are several sources.
What i am doing right now is removing all the TPIC chips and puting them back one by one to understant at what point the problem starts.
I will buy some more caps and follow your advice, but you say 0,1uF and Paul says 1,0uF so i don't realy know which to buy. I'll ask google 