WTF is going on with my sound/LG tv!?!?

Where to start, lol. Ok, I have a lg32lb75 tv that i had hooked up to an xbox and two different cable type boxes - both by hdmi. i then had audio out with red/white component (i think it's called) cable to a cheap old panasonic home theatre in a box. as far as i remember, i had to turn down the volume on the tv and just had it coming out of the panasonic system, but i'm not 100% sure that the sound worked out of the tv speakers. so i have the tv working fine, sound coming out of the home theatre in a box type thing. as of the other day i got a panasonic viera tv, so i unplugged the LG tv and replaced it with the panasonic, everything works fine. fast forward a week and i've decided to go ahead and setup my lg32lb75 in my bedroom but no matter what i use i can't get sound out of the TV, just picture. I've plugged in my blackberry playbook to the tv, picture no sound. same with the a dvd player i tried hooked up via component. i even went as far as carrying it to another room and unhook our optical tv box in that room that i know is working and hooked it up to the tv both with coax and then with component, both gave picture and no sound. so that's a few differen't sources and i'm not getting sound on any of them. i've tried all sorts of different hdmi ports and component ports, turned the tv on and off, checked settings to make sure the speakers were turned on, made sure it's not muted, made sure the tv is turned up, went through all the audio settings and nothing. What is going on here? I guess my next step is to put the LG tv back in the new tv's place and hook it up to see if i was able to get sound out of the tv before and not just the home theatre system. if that's the case

TLDR version (too long didn't read): tv worked with home theatre in a box for sound hooked up with various methods (cable boxes/dvd player/xbox/tablet connected). tv on it's own hooked up with various devices without the home theatre in the box is giving me no sound. Why?

Alright, I just hooked up the tv over it's previous years of use and i'm actually not getting sound out of the TV speakers, just out of the panasonic home theatre system. So for whatever reason i need separate speakers and I assume an amp as well? I wish I had speakers to test without and amp but i'm going to assume it needs the amp. I have no idea why it's like this but if it's not fixable (yes i have tv speakers turned on) then what is the cheapest route i can go? something like the following( is there a built in amp/power source)?

http://vancouver.en.craigslist.ca/van/ele/3527747511.html

It just adds so much more hassle and mess to what i wanted to be a super minimal/simple bedroom wall mount. not only that but all the soundbars i've seen around usually about 2-3 inches wider than the tv itself, which looks a bit weird IMO. It's been so long since I had set up my old setup that I had just thought my tv's volume was turned down. weird. if a home theatre in a box works via red/white component then i'd assume a soundbar will work as well, since they're self powered?

will this work? i assume if it needs to be connected to a power outlet than it's got an internal amp?

http://plug-in.bestbuy.ca/t5/Visit-the-Plug-in-Blog/Review-Insignia-Speaker-Bar-NS-SB212-Enhance-your-TV/ba-p/46010

bump?