I had a chance to mess around with the bluetooth, doing any sort of forgetting devices and powering off/on was not working for me. I narrowed it down to my device (hiby m300) using HD audio.
When the car starts up it autoplays the music (cant seem to find a setting to disable this), as long as I pause until the cutting in/out stops then play it works as you would expect.
I fixed this issue by disabling the HD audio and now when my car starts up the music starts without any cutting on/off. I think this infotainment system just cant handle the hd audio and the fancier codecs like ldac/aptx during bootup.
I don't stream music on my iphone so I cant say but I hear spotify and apple music have options for HD/hifidelity streaming so anyone facing this issue try disabling that.