This issue is not VR releated. It affects all devices, running on OpenSL (with feature:android.hardware.audio.low_latency) audio path.
DUT:
-- feature:android.hardware.audio.low_latency (OpenSL)
-Nexus 6 / 6.0.1
-Nexus 5 / 6.0
-Nexus 4 / 5.1.1
-gNexus / 4.3

-- no feature (JavaTrack)
- HTC ONE V / 4.0.3
- SGS2 / 4.1.2

Steps to repro:
0. Connect Bluetooth audio speaker/headphones to the device
1. Build and run any audio project (I've attached one)
2. Notice after app start that sound stuttering

Important! Sound stuttering only when device using OpenSL audio track. Tested with Unity 5.3.1p3. Before OpenSL impl., i.e. Unity 5.1.4p1 bluetooth sound is not stuttering. You may treat it as regression.

All logcats are attached.
Stuttering sounds with different DSP setting are attached as well.

Project is here: https://oc.unity3d.com/index.php/s/Rp1oCEBaLmFYZ07