Comment 2 for bug 1504057

This gets a bit tricky when you want to define what actual "traffic" you want to indicate. Just count HCI frames on the link doesn't make sense as those don't mean anything goes to a remote device.

This should be more or less happen on a per-profile level. When a profile becomes connected this needs to be indicated somehow. I've pushed support for this yesterday upstream (see http://article.gmane.org/gmane.linux.bluez.kernel/64957). This is something we could reflect in the indicator details or in the settings app. The indicator icon should only reflect that bluetooth is turned on and that we're connected. IMHO putting more details into this tiny icon just overloads it with too much details.

The other part is for the special use case of a profile. Indicating that we're playing music is really up to the sound indicator. If you want a clearer indicator where your audio goes to than this needs to be reflected in the sound indicator too. We don't have the option for the user right now to switch between speaker, earphone or bt audio when playing music. A2DP currently gets the highest priority here.