ThoNohT said:You aren't dropping frames, the encoder is duplicating frames. The most likely problem is that you put your x264 preset to slow, which is insanely heavy on your system and never recommended for livestreaming. Definitely not with a mobile i5.
Move that preset back to veryfast, as the warning sign told you when you changed it. Another issue might be that you are on a multi-gpu setup, check this thread for info related to this: http://obsproject.com/forum/viewtopic.php?f=5&t=5965