Lost stderr and stdout

When working in Jupyter I sometimes loose stdout and stderr. It seems to be piped somewhere else. This happens usually after making syntax errors in numpy, pandas or ROOT. It does not seem package specific. And I can't recover it using

import sys
sys.stdout = sys.__stdout__
sys.stderr = sys.__stderr__

Since I don't have any error to show I don't really know how to describe it in more detail, restarting the kernel gives it back. This happens in both Jupyter notebooks and Jupyter lab.