What about some IEMs with a Bluetooth dongle? (ifi goblu, Fiio btr etc?). I’ve got sennheiser ie600s with an iFi goblu for travelling (both bought from SC as it happens) I also have an audio quest dragonfly black with Apple cck to plug directly in if no battery to charge the goblu. Small, convenient, easy to charge and fantastic sound (also comfortable too, no sweaty ears).