Cannot play mkv files anymore??

Hi guys
I need a bit of a help. I remember that when serviio was 0.90 or something, my TV could play mkv files without any problem but now it doesnt seem to be the case. I dont know what I have done wrong (I've updated ffmpeg version?) or something but none of the previously mkv can be played. The profile is selected as KDL-40CX523 which is the TV.
I can play mp4 without any issues.
Could someone help please?
Thanks
I need a bit of a help. I remember that when serviio was 0.90 or something, my TV could play mkv files without any problem but now it doesnt seem to be the case. I dont know what I have done wrong (I've updated ffmpeg version?) or something but none of the previously mkv can be played. The profile is selected as KDL-40CX523 which is the TV.
I can play mp4 without any issues.
Could someone help please?
Thanks