I've had LOTS of problems with the sound on my Cosmos 2!! I don't even have an earpiece that fits it....which makes it even harder to hear callers. I put them on speaker, but that does little to help. Heck, we can't even get a good signal here & the Verizon map says it's the BEST signal in town! Yea, right! I'm about ready to go back to a land line, just to be able to hear my callers again! What a giant step backwards THAT would be!