Double subtitles on Panasonic ET5

Hello! Subtitles are now showing but they seem to be superimposed with the same subtitle. You can see the difference between them is not large but you can still see the same subtitles twice one higher than the other one. What option have i misconfigured? Thank you for any help you can offer me. I just began using Serviio yesterday (as well as the ET5 TV) so consider me a noob.

Updated to V. 1.2.1 after reading the release notes but the double subtitles are still there. At least for me, it doesn't seem to fix the issue.

[zip]

can you post detailed log of playing the affected file?