I try to load a TS-record of HD TV:
Video: Video - AVC (H.264), Main Profile, Level 4.0, 1920x1080, 25.000 fps
Audio: MPEG1 - Layer 2, 48.0 kHz, 2 chn, 192.0 kbit/s
Avidemux 2.6.4 write: "Cannot find a demuxer for filename.ts"
Is it normal or bug?
No it is not. On daily basis I'm using these mpeg-ts videos. You should update to the latest avidemux 2.7.1 . Avidemux 2.6.4 is a little dated.
Try one of these https://avidemux.org/nightly/
If you would still have an issue with these, provide a 10 second of such recording (Upload Hochladen Télécharger Subir (http://avidemux.org/smif/index.php/topic,17418.0.html)). So we can see it is the recording or something locally.
PS: don't try to spam this board again as you did with your 1st posting