Three suggestions:
I'd suggest upgrading both phones up to 1.1.2 - This cures many small bugs and crashes. Gives you Ringtones you can sync with iTunes and more.
If they're unlocked:
http://www.everythingicafe.com/forum...2-a-18267.html
If not unlocked follow this guide
http://www.everythingicafe.com/forum...one-18919.html from the paragraph that begins: "Once this is installed you will see installer on your home screen of your iphone.. Click this and go"
Search for speaker volume concerns - loads of options. Someone asked the same question today already.
Your brother may or may not be able to downgrade to 1.1.1. I can't personally see why anyone would want to do that apart from as a half-way step to some other state.