UMIDIGI A5 Pro wifi problem. wifi gets lagging with bluetooth earphone.

Youtube video is too slow to watch when I connect bluetooth earphone to UMIDIGI A5 PRO smartphone. This phone has a serious wifi problem. other than this, This phone is ok for the price. If I don't connect bluetooth earphone, youtube video is fine but wifi is not as good as famous branded smartphone. Be aware of this when you buy UMIDIGI A5 Pro.