Cannot set ringtone to vribate with headphones in

I have an S6 5.1.1.

With headphones in, when i turn the volume of the ringtone to vibrate only it immediately goes back up in volume to the lowest setting. I have force stopped soundabout and i am able to get the ringtone to vibrate with headphones in.

Any help/advice?

Have you set any settings in SoundAbout / "Alert behavior" / "Wired Headset behavior" ?

My guess is that the "Notification To" is set to Headset (override). This means that a headset being plugged in will cause a notification so it can't go into vibrate or silent mode.

New versions have just been uploaded to Google play that will address various issues like this.

You can get them now from the Beta section located here (need a login to the message board).  There is also Betas for SoundAbout and SoundAbout Pro.
https://soundabout.forumotion.com/f8-download-beta-versions