Hi, 

I've just recently bought the Acton II to have as a speaker in our bathroom. Looks great and sound good enough. So far I'm satisfied. 
However, the speaker is driving me mad. Here's why. 
My girlfriend and I both use the speaker whenever we're spending time in the bathroom, so both our phones have been connected to the speaker at some point. 
But, if I'm playing music from my iPhone to the speaker and my girlfriend is in another room, let's say, watching YouTube on her iPhone things get wierd. If she adjusts the volume on here phone it also messes with my music in the bathroom. 

Another example:

Playing music from phone 1 to Acton II. then, Adjusting the volume by using the buttons on the side of iPhone 1 also adjusts the main volume of phone 2. Even though Phone 2 isn't in use. It just messes with the volume of it. 

This is suuuuuper annoying. Since the app is no where near of being good, I don't know how this can be solved. If there's no good solution I'm gonna have to sell the speaker and buy a brand that really knows how to make speakers for this purpose. 

Does anyone know if this can be fixed..??

thanks / Mathias