"68 hours of playtime from just 1.5 hours of sunlight"
Two and a half days ? I call bollocks on those numbers. First of all, I don't believe that wireless headphones can last 68 hours on a full charge, full stop. Next, I seriously doubt that a small band of photovoltaic cells can recharge whatever battery it has to 100% in a mere 90 minutes - even if you live at the Equator in the middle of a drought.
Somebody post some figures that are more realistic.