Resolved......without having to buy/replace ur evo......first of all I work for sprint corporate and whoever told u it was a hardware problem is either new, lazy, or just wants u to have to take hours reseting ur custom evo again...(who's to say ur not goin to have the same issue again....u think they'll replace it everytime) NO..... here are the steps to fix both speaker phone annoyance and volume control with any head sets..
First yes u are correct the dock thinks ur on the car docking makin the speaker phone default even when ur not...and also sets the headset volume to middle regardless.....soo you were correct...BUT..ur wrong if u want to hard reset ur device or replace evrytime u have an issue.....
1. U go into Bluetooth feature on settings..wireless .(if u set ur Bluetooth prior ur mostly having this issue)
2. Turn on Bluetooth ....if u are paired but not connected then go to the device u have set up.
3. Go ahead and tap it for about 3 seconds til it shows u options. Unpair, connect, options.
4. If u aren't using it at the moment...then click options then unselect both media and phone then turn off Bluetooth ....
5. Enjoy life without have to press speakerphone off and being able to turn up if media like Pandora media or music....
Just keep in mind if ur plugged into the larger its not goin to work for u...cause it thinks ur in the car...unplug and Ull be able to do everything