Command Block Faulty Power

I tried to make a repeated particle effect by making a redstone clock with a piston, block of redstone, and some redstone dust and comparators, the delay was 4 and I used 3 repeaters, 1st 1, 2nd 2, 3rd 1; if it helps.
I tried to split the power so it could power the command block repeatedly with 4 ticks in between each pulse. I placed the redstone wire on top of the command block to complete the circuit, and it worked, but then I saw that the command failed and realized I forgot something in the command, so I changed it. (I was using </particle>) Turns out, once I changed it, and the next pulse powered the command block, it froze! I think it had something to do with the redstone dust on top of the command block.
Hope you can help.