Problem with MicroDVD-subtitles

Hey!

I have a strange problem with .sub (microdvd) subtitles. They work well, except that they doesn’t show at the beginning of video. After waiting for a while (between a minute or ten minutes), they come up and work well for the rest of the video. Strange is, that if theres a lot of talking in video (and therefore a lot of lines in subtitle file), subtitles comes up earlier than if theres no lines in the beginning of the video. So it is not a connection issue. SRT-subtitles work fine. Issue is with every episode I’ve tested.

My kodi log: http://paste.osmc.io/daxipokiqa.vhdl
Issue is there with Game of Thrones, Modern Family episodes and 12 years a slave (.sub subtitle), but 12 angry men works well (srt subtitle).

Device: (Rasp Pi B
Installation media: SDcard
Connection: Wired
Peripherals: None
Storage Device (incl. Network Sharing Protocol): FTP in local network
OSMC version: July 2015.07-01
XBMC version: 15.1
Codecs: (h.264)
Audio/Video Output: HDMI
Overclocked: High profile
Config.txt Extras:
arm_freq=950
over_voltage_sdram=0
over_voltage=6
core_freq=450
initial_turbo=0
start_x=1
sdtv_aspect=1
disable_overscan=1
gpu_mem_256=112
gpu_mem_512=144
force_turbo=0
sdram_freq=450
hdmi_ignore_cec_init=1