SS IPTV

hi,

i'm having trouble playing http unicast streams in ss-iptv app.
the playlist is loading both in local or external playlist, channels appear, but non of them plays.

my playlist consists from this sort of channels:

example channel
http://x.x.x.x:YY/udp/23x.x.x.x:1234

also, tried different sort of playlist, like m3u_plus with ts output from one provider and those work.

also, the playlist with problems works flawlessly in vlc with the same isp, so i wouldn't consider a isp issue

any help or advice would be much appreciated