[ISSUE] Stuttering when loop empty sound

Hello,
we just saw something really weird today in our project.
To earn time for a later update we put a lot of placeholder sound in our game that was just empty sounds. But in some case we saw a weird issue with them.

When you try to loop a sound which is a 0 length sound it will create stuttering issue on our other sound particularly our ambiance sound which is streamed in background (music).
Then when we try to stop it, the sound is never released from our pool system. It's the first time we experienced an issue with our pool sound system in 2 years so I think it's an issue from the engine.

We currently use Unity 5.3.7.

I will check the sound state when he's still here but not stopped. But I think it's an issue between empty sound + loop.