Very difficult. The chirping is due to the pick attack being interpreted as a high pitch.
One approach I've tried is dynamic filtering (i.e. alpha-beta trackers, etc.) for the pitch but that introduces other problems with the pitch sliding between notes. It's a limitation of the technology. Real-time pitch detection is simply limited in what it can do.
The best solution is to alter your technique to minimize pick attack.
the synth block gets it's pitch info from the main input