stream.mp3 sequence question

I use logitechmediaserver 8.1.1 on Ubuntu 20.04, normally streaming to a squeezebox duet.
Occasionally I open the stream.mp3 page in opera on my smartphone and stream to that too.
When I start the stream.mp3 I can choose that as a player on the mediaserver web gui.
It also remembers the last used playlist.
I have 3 albums in a playlist and I do not use shuffle mode.
When I initially did setup the playlist, the stream.mp3 did play all the tracks in the correct sequence.
So far so good.

Today I re-opened the stream.mp3 and selected the stream as a player.
I selected the 1st track of the 2nd album of the remembered playlist and reloaded the stream.mp3 page to force it to start with the stream at that track.
It started with the selected track and played the next couple of tracks in the correct sequence, but then skipped over some tracks.

I do not understand why this happens.
Is there some caching going on?
If so, is it the opera browser cache or a cache on the squeezeboxserver?
I may need to clear the browser history on my smartphone but then I will loose other history too.