Autoupload and permission

Hello everyone.

I’m using Nextcloud (18.06) on an odroid XU-4 (ubuntu 18.04).
My files are all on an external HDD plugged to the odroid, everything works fine

I also have a Plex server which is linked to this hard drive. The idea is that when I upload a file (photo/movie) on nextcloud, it will be automatically added on plex.
Thing is that when I upload a file through autosync with my android phone - basically when I take a picture and its autosynced - the file is uploaded with permission 640… But I need it to be 755 in order for plex to be able to add it to its library…

Is it something I can change ? Any configurations ?

Thanks for your help.