Midi problems, stuck notes, please help

My setup is keystep to octatrack midi in ,octatrack midi out to organelle , some of the notes get stuck when I play on the keystep thru octatrack to organelle …

When my midi output from octatrack goes in to septavox and septavox midi out to organelle ther is no problems at all,. But can septavox hold midi fr other channels then 1 ?