@fabinthegreen I checked lt, and indeed, on the Box for a lot of channels the subtitles are taken from the respektive teletext (if available) For the Blue TV App or Blue TV Air on the PC, this is not the case, as these media do not support teletext. To be honest, at the moment I have no idea why on the box this is different. However, on the box it is not possible to change this, you can just choose the version which is offered by using "option" and "subtitles" with the RC.
I will raise this question tomorrow morning in the German-speaking forum and contact the specialist for the TV box there. Perhaps it can be adjusted on the system side of the box. I will keep you informed.