WD Live TV + WD Book Live = SRT problem

I have a WD TV Live Media Player wired to the router, also I have a WD Book Live wired to the same router. 
When I play a MKV file with a SRT file (both with the exactly same name) I doesn’t show the subtitles. 

I thought it wasn’t possible to do it…but I have a Samsung Smart TV in other room (wireless connected) and I can see the subtitles of the same MKV file located in the same WD Book Live. 

The only difference between the Samsung TV and the WD TV LIve Media Player is how they are connected to the router. 

Any ideas? Thanks!

I avoid those issues by muxing the SRT into the main mkv. a good program for this is mkvmerge. The windows front end gui for this is MKVToolNix. Search web fo MKVToolNix.  If you always want the subtitle, you can set to forced or default.  You can also “burnin” the subtitles with Handbrake.

Connect via network share instead of media server and the WDTV will display the external sub.

OK, but when I choose Network shares I see nothing, should I do something on the WD Live Book? Thanks

Put WDTV and MyBook into the same workgroup.

They are in the same group.

I solved finally installing the WD Book Live again.

Thanks a lot!