How to attach events to AAMP Player?

I have this(above image) player page code which plays Dash streams using AAMP Player, I want to attach events to aamp player(following this document) so that i can add loader and some placeholder image as the background while the stream loads and hide it when video starts playing and vice versa. I added as mentioned in the above document
this.player.addEventListener('playbackStarted', (e) => { this.tag('Background').alpha = 0; this.tag('Title').alpha = 0})
to hide the backgorund and title and show the stream but this event listener is not working, did anybody else faced this issue, if so how to resolve this? Please help.

Thanks.