1st post, sound doesnt work after using MKVfix

hi. I have a WD media player gen1 or gen2, its about 3yrs old. I have been having problems with HD files only, downloaded from internet. I have recently decided to do some reading up and sort these files out. I have downloaded MKVtoolnix, MKVfix and Mediainfo as recommended on other posts here. I ‘cleaned’ the files using MKVfix. This showed that header stripping had been removed from the mediainfo report. The video works fine but I do not have any audio through the media player. Audio works in VLC.  Any advice would be much appreciated, thanks in advance!

Please post the full TEXT output of MEDIAINFO for such a file.

http://mediainfo.sourceforge.net