@Solla-topee many thanks for your replies. I have tried to email you as requested, and send you a link to a video clip, by replacing "community" in the tp-link notifications email address with "solla-topee" as I thought you were requesting, but the email bounced back to me.  For now, here is one section of it: 

1.     Re:Grinding noises from motor

Grinding may have been the wrong adjective – probably more a buzzing/squeaking but it only really seems to be an issue at the commencement and end of a horizontal pan movement with no sound when tilting.  I have uploaded a cropped playback clip to google drive which was recording during manual pan/tilt movements. 

At the commencement of this clip there is some silent tilting, and then the noises which I am trying to describe with the horizontal movements.  The auto pan/tilt full readjustment selected from the menu options in the app generally operated very smoothly with just a normal whirring of the motor during the horizontal panning and no sound during the tilting phase – apart from a little at the maximum tilt position as though further movement is being resisted.  However, the first time I tried the pan/tilt auto readjustment there was a “clunk” after the first horizontal motion.  I am guessing this is because the camera position did not begin in its default position, as when I tried the pan/tilt auto readjustment a second time, this did not happen.  Would this be a correct assumption?

Assuming you still need further information, please let me know how to email you further details and the link to the video.  Kind Regards.