Why cant I get an ear phone to work with the ONE XL

I have a ONE XL. I need an ear piece so I can hear while ridding the motorcycle... Please help.. I have tried to find an answer on line but cant figure out if it will even except an ear bud. I am leaving for the trip of the life time to Sturgis SD in a couple weeks... I need to be able to hear directions while ridding with a helment.. An ear bud works fine with the motorola phone in the right ear... I want to hear from tom tom in the other ear... Please help... I've tried every connection there is and still cant get sound from anything but the speaker in the tom tom...