Do you have these problems, when we play 720P/1080P Blu-ray MKV videos on Galaxy S2, there have image but no sound, or have sound but no image. Galaxy S2 is a powerful smatrphone, also a amazing movies player. Galaxy S2 can play MPEG4, H.264, H.263, WMV, DivX, Xvid, VC-1, MP3, OGG, AAC, AAC+, eAAC+, AMR-NB, AMR-WB, WMA, WAV, MID, AC3, IMY, FLAC, XMF format files, The most amazing is Galaxy S2 can play 720P and full HD 1080P Video, but why have 720P MKV video problem on Galaxy S2, no matter the MKV where is from, We must know the MKV is container format, if the video codec and audio codec is not Galaxy S2 supported, then Galaxy S2 can not play MKV files well. How to play MKV movies on Galaxy S2 well? We must change the MKV’s code.