SWF player starts playing from Frame 2 instead of Frame 1

Hi,

I've made an interactive animation using Adobe Animate and Action Script 3.0. The main timeline has two layers, one of which is the Action Script. The timeline has 6 main frames, each one of them with a .stop(); attached to it in Action Script.

I'm currently having an issue playing .SWF files through multiple external SWF players (Swiff, GOM and MPC). When I open the .SWF file, it starts playing on Frame 2 instead of Frame 1. On Frame 6 (the last frame), there's an option to go to Frame 1 again. This actually still works in the external SWF player, yet it won't play from the very first frame when opening the file. For some reason it recognises Frame 1 as Frame 0, and Frame 2 as Frame 1, and therefore it won't play from the actual first frame.

Does this have anything to do with my publication settings perhaps?