Turned on computer, date changed and no audio

[Vaimahina]

Ok, so this morning i turned on my computer and the date for some reason changed to Dec 31st 2014 at 10:00 pm. The audio is also no working, internal speakers and headphones both no sound. I inserted an Apple headphone jack several times, checked the sound settings, quit coreaudioid in Activity Monitor, reset PRAM and SMC, all with no luck. I'm not sure if the date change and sound problem are related. A week ago I plugged in external speakers and the audio went and then came back when I re-plugged it (not sure if it's related or not either). Also, the jack gets VERY hot when charging the computer when it's turned on. This has been happening pretty much ever since I got it (again, not sure if it's related or not, or if it's even normal, since it has been that way from the beginning). The MagSafe isn't damaged at all. The computer is less than 2 years old and I got it after my earlier MacBook Pro had a logic board problem before it was a year old. I live in Easter Island which means the nearest Apple place I can take it to is 3,900 kms away. The computer is running on Yosemite 10.10.5; I haven't been able to upgrade to El Capitan because the Internet on the island is very slow and the download keeps getting interrupted. I hope someone in this forum can help me, and I very much hope it's not a logic board problem again.