I asked DH, the wonderstud of corralling cables, and the only thing he could think of that would work in your situation are these Velcro cable ties.

They attach right to the cable then whenever you want to take up slack you figure 8 some cable, wrap this around it, it stays put. When you want to let some cable out, the reverse. We use these a LOT around the house for things like electrical kitchen appliances that get stored, otherwise the cords drive me mad. Also on extension cords that get pulled into and out of use periodically, and other electrical things where we want to take up the slack so that things don't get tangled or in the way. He gets his at the hardware store.

Good luck!

Anhata
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