I so often forget to plug my audio interface in.
I then get an error dialog saying:
 
"SONAR Platinum"
There are no audio devices for the current driver model on your
system. Please go to Edit | Preferences | Audio | Playback and
Recording and choose a different driver model.
 
So I go "Ah! Expletive!" and plug my interface in. But it's too late.
 
I now have to say OK, wait for Sonar to start, be told Silent Buses Detected,
that Master is assigned to a silent hardware, say OK, wait for the project to open,
close the whole shebang, restart and only THEN is my interface recognized.
 
How about automatically re-checking for an interface if the user plugs one in
on the first error dialog?

Voted. It happens so many times here and I really hate it.
A competitor daw allows me to connect the interface and then retry without restarting the program. Sonar doesn't.

Yes!
This makes me crazy!!!

+1 .. YES.

+1 this would be a great feature for me

+1

I have a similar problem always when I set my laptop into sleep mode. As soon as I wake up the system, I get a message from Sonar, although the same USB audio device is still connected:
 
TASCAM US-144 MKII
The above Audio/MIDI device was disconnected from your system.
Would you like SONAR to reroute these outputs to an available device?
Clicking 'No' allows SONAR to remember output settings to this device.
Note: If playback is in progress, clicking 'Yes' will stop the transport.
 
If I press 'No', then most of the times the audio runs properly again, but sometimes there is no other way than restarting SONAR.