Panasonic TX-L42ET5B aspect ratio problem

Hi all this is my first post so forgive me as i am a noob to this stuff, I have ben using tversity through my xbox to stream to my old analogue tv without problems, i have just purchased anew panasonic viera 3D smart tv model number in the title, I have started using serviio to stream directly to the TV via wireless but i cannot change the aspect ratio for a lot of movies i have downloaded it is frustrating enough that i just turn them off and delete them, this is wastefull so i wonder if there is a solution. The last straw was when i sat down to watch savages tonioght and the screen filled up and everybody head looked stretched up and down not in 16:9 like i want, these are some details from the nfo of the movie download
Video.......: X264 4030Kbps
Frame.Rate..: 23.976
Resolution..: 1280x536
Audio.......: DTS
Language....: English
Length......: 2h 21m
Source......: Retail Bluray
Size........: 5600MB
it's a Matroska video whatever that means and it's 5.5 gigs in size. also does anybody know what files i cannot watch because it's a bit hit and miss. the movie is in video format so my tv tell me

[zip]

Can't you change the aspect ratio via your TV remote? Post ffmpeg -i of the file and which profile you're using.

ratios on the tv don't fix it and i don't understand any of that ffmpeg stuff mate. i bought a media player instead, plays everything without a problem

just checked back in to see if anything has changed I still use servio to play tv shows which it does brilliantly but I downloaded a new movie last night and it stretched it to the top of the tv and the aspect ratio on my tv will not change it. I stuck it on the plug in media player to watch but i would still like to use servio as it's handier.

[zip]

if the file is remuxed, your TV can't get the aspect right. You could try disabling transcoding. Or edit the profile so that it transcodes the file, instead of remuxes. There might be some tips already, so search.