Comparator giving off wrong signal

As usual, a comparator will be activated when a command in a command block is met. My bug is, when i cut the signal going to the command block, the command stops running, but the comparator won't turn off. I would have to either replace the command block, or just go into the command block then click "done" to turn it off. I can't just destroy the comparator and place it back because as soon as I place it again, the comparator signal will run true. I'm not sure if it's a bug, but most of my redstone contraptions won't work until this problem is resolved. Here is a picture...