Some observations have very high "streak" count rates. The default tool parameters may not clean all of them.
For some observations with very high streak rates, the 'max_rowloss_fraction' may need to be increased to remove the excess noise. Setting the parameter max_rowloss_fraction=1.0e-3 may help to remove the excessive streak noise. However, users must be extrodinarly careful, especially with Gratings and CC mode observations that real events are not removed.