Merging .srt Greek subtitles with .mkv

[wolfmandim]

I have been watching .mkv movies with external .srt Greek subtitles successfully so far. Lately, I tried to permanently add those subtitles to the .mkv using the MKVtoolnix 4.2.0 merger. The subtitles will display fine during playback, however, with a slight problem. Some letters from the beginning of every phrase are cropped.
I forgot to mention that I am using the latest version of BSplayer pro (2.56.1043). I tried both Windows media player and Windows classic player and and the subtitles display fine on either of them.
How can I correct the problem on BSplayer pro?

[adicoto]

A workaround is to change the font from....as an example Arial to Times new roman.

[wolfmandim]

Originally Posted by adicoto

A workaround is to change the font from....as an example Arial to Times new roman.

I tried it. Changed fonts to various types, also changed the size of fonts. Still, the same problem..

[adicoto]

Some solutions can be found here:

subtitles are cut off left and right (cropped subtitles)