If you are within the 30 return window through PayPal and ebay I would return it as new defective for refund or exchange. Personally I would choose refund and rebuy if the price is close. Who knows how long it would take for repair or replacement...
Mostly stills maybe 10- 20% for video. I am coming from a Phantom 4 Pro so this is huge. Verticle on real estate is a big help. Most of the lots in my area are narrow and front shots in landscape gets the neighbors homes. Less editing and better...
I have tested 3 M4P's and haven't had any of the symptoms above. The gimbal even with limitations in portrait mode is one of the reasons I bought it. I like having full resolution in portrait. Works great for landscapes and my real estate...