No audio on fire stick on my DVD rip mkv

[pollik]

I've ripped a DVD for the first time, I've used makeMKV and made some .mkv files. 

They play fine on my laptop in both VLC player and Jellyfin, but using Jellyfin on my amazon fire stick on the TV it only plays the video - no audio comes out. Weirdly this then also stops audio working for everything on the fire stick until it is reset.

Everything else plays fine on Jellyfin on the amazon fire stick.

Anyone got any ideas as to what I've done wrong here?

Jellyfin tells me the .mkv has the following properties:

Container: mkv
Size: 4009 MB

Audio
Title: Mono - English - Dolby Digital - Default
Language: eng
Codec: AC3
AVC: No
Layout: mono
Channels: 1 ch
Bitrate: 192 kbps
Sample rate: 48000 Hz
Default: Yes
Forced: No
External: No

Subtitle
Title: English - Default - DVDSUB
Language: eng
Codec: DVDSUB
AVC: No
Resolution: 720x576
Default: Yes
Forced: No
External: No

Video
Title: 576p MPEG2VIDEO SDR
Codec: MPEG2VIDEO
AVC: No
Profile: Main
Level: 8
Resolution: 720x576
Aspect ratio: 4:3
Anamorphic: No
Interlaced: No
Framerate: 25
Bitrate: 5956 kbps
Bit depth: 8 bit
Video range: SDR
Video range type: SDR
Pixel format: yuv420p
Ref frames: 1

Audio
Title: Mono - Nor - Dolby Digital
Language: nor
Codec: AC3
AVC: No
Layout: mono
Channels: 1 ch
Bitrate: 192 kbps
Sample rate: 48000 Hz
Default: No
Forced: No
External: No

Audio
Title: Mono - Swedish - Dolby Digital
Language: swe
Codec: AC3
AVC: No
Layout: mono
Channels: 1 ch
Bitrate: 192 kbps
Sample rate: 48000 Hz
Default: No
Forced: No
External: No

Audio
Title: Mono - Danish - Dolby Digital
Language: dan
Codec: AC3
AVC: No
Layout: mono
Channels: 1 ch
Bitrate: 192 kbps
Sample rate: 48000 Hz
Default: No
Forced: No
External: No

Audio
Title: Mono - Finnish - Dolby Digital
Language: fin
Codec: AC3
AVC: No
Layout: mono
Channels: 1 ch
Bitrate: 192 kbps
Sample rate: 48000 Hz
Default: No
Forced: No
External: No

Subtitle
Title: Nor - DVDSUB
Language: nor
Codec: DVDSUB
AVC: No
Resolution: 720x576
Default: No
Forced: No
External: No

Subtitle
Title: Swedish - DVDSUB
Language: swe
Codec: DVDSUB
AVC: No
Resolution: 720x576
Default: No
Forced: No
External: No

Subtitle
Title: Danish - DVDSUB
Language: dan
Codec: DVDSUB
AVC: No
Resolution: 720x576
Default: No
Forced: No
External: No

Subtitle
Title: Finnish - DVDSUB
Language: fin
Codec: DVDSUB
AVC: No
Resolution: 720x576
Default: No
Forced: No
External: No

Subtitle
Title: Ice - DVDSUB
Language: ice
Codec: DVDSUB
AVC: No
Resolution: 720x576
Default: No
Forced: No
External: No

Subtitle
Title: English - DVDSUB
Language: eng
Codec: DVDSUB
AVC: No
Resolution: 720x576
Default: No
Forced: No
External: No
Audio
Title: Mono - English - Dolby Digital - Default
Language: eng
Codec: AC3
AVC: No
Layout: mono
Channels: 1 ch
Bitrate: 192 kbps
Sample rate: 48000 Hz
Default: Yes
Forced: No
External: No