Sena Intercom

Does anyone have a Sena 10U intercom? I have one and the battery life is maybe 4 hours max. Sena are telling me that it should be at least double that but looking in T'internet it seems that 10U battery life is not good in general. Mine is still under warranty (just) so I may well be able to get it replaced as Sena US have suggested. I was wondering if it is possible to get a longer lasting battery if I can't get it sorted by Sena.

 

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