Lekato MS-1 - wireless adapter for headphones. Then get a wireless system for the bass (Lekato do a few of those too). Alternatively, as I think someone recommended on page 1, a Nux Mighty Plug.
On the left, Nux Mighty Plug. On the right, Lekato MS-1 at top and Lekato WS-50 underneath (the Tx and Rx labels are mine, easier than trying to read tiny lettering in the dark).