Is there a way to control which audio is sent to Bluetooth and which is sent to system speaker? Background info explaning why I want what I want

I'm almost totally deaf. I have a Bluetooth-enabled hearing aid that is paired with my Droid RAZR (ICS 4.0.4). When any audio is played on the phone (ringer, phone call, media, etc) it triggers my hearing aid. The switch-over is not instant and I miss a few seconds of audio (plus I get a really loud, annoying beep from my hearing aid informing me that it is making the switch from external audio to BT audio).

As a result, text messages and other short audio notifications (like navigation speech) trigger my hearing aid, the loud beep occurs, the external mic is turned off, the BT connection is enforced, and then... nothing. In the time it takes for all that to occur, I've missed whatever the audio input was.

TL;DR

I'd like to be able to tell my phone to direct text messaging, ringer, and other audio playback (navigation) to the system speaker and to continue to direct in-call and media playback to my paired, BT-enabled hearing aid. Is there a way to do this?
Try BTmono,   maybe it helps.