How do I make the sound work on my Google Talk / AIM / MSN / Yahoo / Skype?

I have a Lenovo Y530 Entertainment PC equipped with a webcam and a microphone. I am both transmitting sound and video. However, with programs ranging from (yes, I've personally tried them all) Google Talk to AIM to Yahoo to MSN to Skype, I can NOT receive sounds. I would say it is the other persons sound problems. However it occurs with ALL makes and models of computers. I quite simply cannot hear the other person's sound. I have tried going into my audio settings and checking it to play on "RealTek Speakers" and on "Default Devices" and all the options. I can receive video, for the record. Just not audio. Also, it shows in, AIM and Google Talk for example, that the other person IS talking. It shows the little Audio dB level thing moving up and down based on the other person's talking. It just will not come out of my speakers! I have also tried plugging in microphones. Please help. Please.
How do I make the sound work on my Google Talk / AIM / MSN / Yahoo / Skype?
I suggest you run windows CUSTOM updates and if it offers something to install, just read about it first before deciding to go ahead. Hover the mouse over it.





click start %26gt;all programs %26gt;windows updates located up at the top.