A week ago a bubble popped up on my desktop offering to clear space because i was running out of memory on my computer. I clicked it (shouldn't have) and it "cleared space" but now my computer won't play any sound. i have Dell speakers and they work fine because i can plug them into my ipod and play that. I already did the Control Panel-Sounds and Audio Devices-Audio tab but once I get to the audio tab this website tells me to click "Advanced" under "sound playback". However, I don't even have the option of clicking that button. it won't let me click it. Also, there is no Volume control icon on the bottom right corner of my screen (next to the clock). like there should be. I really need help