Why is there no sound in the speakers, only in the earphones?

Your laptop is stuck in digital audio mode, and thus the red light. Take the cotton off one end of a q-tip, and while the laptop is still on, put this in the headphone jack and twist repeatedly. Watch the audio indicator in the upper-right of the screen as you do this. When you see it turn black (instead of being greyed out), remove the q-tip. Often, it will grey out again, and you must repeat the process until, finally, the icon stay solid black, and the red light remains off. The process can test your patience. You can also use a paperclip or a thin screwdriver, but I hesitate to recommend inserting a piece of metal into a laptop that is turned on.