Can we please look at an example using the information requested above? thanks.
I will provide step by step instructions on how to reproduce this bug.
I am running Xteve handling the m3u but regardless of that it still holds a slot on a direct connection to my provider.
1) Open chrome on your computer (I am using windows 10)
2) Head over to your emby server.
3) Open a live TV M3U channel.
4) Before the stream loads while there is a swirl loading symbol pre-buffering the video close chrome the tab. (This part has to be done quickly before the video loads)
5) That is it. If you would like to confirm if reproducing the bug worked follow the steps below.
6) check your IPTV provider or Xteve to see that the stream is still open using up a slot.
7) Check emby activity section and displays no streams running meanwhile if you check your trascoding cache folder properties it is being continuously filled.
To stop the bug reboot emby server cache will be emptied and stream will be terminated.
If this fails allow a few more seconds of pre-buffering on step 4
This can be repeated until every slot is full on your iptv
I have not tested this bug on other devices yet but I do believe it is happening with changing channels mid buffering (not confirmed)