How do I disable the triple vibrate of Viber? When I get a notification in Viber it vibrates three times, as well as playing the sound. How do I stop it from vibrating three times!? 

I saw the question about receiving multiple notifications but that doesn't apply as I don't use Viber for SMS.
In version 5.3.0 for Android, on my HTC one m8 I couldn't find ANY option to disable vibrations, exept for the "incoming Call" one. 
So my phone sounds one time and vibrates 3 times when I receive a message...

Later edit: Just wrote Viber, they answered that a fix will be available shortly !