For those who do not own this spectacular bird: it has two "layers" of sound. The normal P3D sounds which go the the rift earphones automatically, and the PMDG sounds. The latter ones have to be directed to the rift earphones via the 747´s FMC sound menu. Together, it gives a fantastic environment. However, every few minutes the PMDG engine sounds cut out for some seconds. I have already looked up the AVSIM PMDG forum. Does someone here know how to solve this odd problem?
Edit: P3D native VR does not produce the sound cut outs.
Michael