But often although set to notify it does not make a chirpy at all.
For instance, using my phone this morning kinda early before 8am, browsing Facebook, when finished I noticed I had a what's app message. That should have maid noise-ringer, excetra.
Not noticed this recently, there were a few problems on previous betas. Are you fully upto date on beta 3. Are you using DND that maybe blocking notifications for certain apps?