PhatBox cables rattling in the back, need solution...

[Number54]

I have a B5 S4 with a PhatBox mounted in the trunk and I discovered the cabling was bouncing around and causing a rattle. I tried zip-ties, but once the mounting frame is installed, I can't get behind it to secure the cables perfectly.

The stock wiring has a section enclosed in a styrofoam cylinder. Anyone know where I can get that stuff? Or a better solution?

Thanks.

[GotRS?]

Check out your local hardware store for the insulation for water pipes, the one for 1/2" pipe might do it.