Saw a spark plugging in your InterBass? That's normal

When you "hot-plug" a live PS-24 into the 24V DC input, a small spark is completely normal and harmless. If you'd rather avoid it, the trick is to plug the DC jack into the unit first, then apply AC power. And be sure the DC plug is seated all the way in. (This applies to the discontinued InterBlock 45 as well.)