BleepingComputer.com: Problem about audio device installation

Guys, please give me your expertise on this matter!
Recently, I encountered this audio problem of computer. I wonder that everytime I play audios, I can't hear any sound. I tried already the control panel stuff and searched the web for some help but nothing helped me on that. I already downloaded a freeware from Realtek and installed it. I am positive on that because I thought it will help but there is still wrong with my computer. It said that it can't copy RTKVHDA.sys. So, I downloaded RTKVHDA.sys. But after that, it said that "setup cannot copy the file RtHDVCpl.exe". I'm so tired of fixing this. Is RtHDVCpl.exe a virus? or an error? Please help me, guys!
I'm looking forward for your advise on this!
Thanks a lot!

System manufacturer and model?

Louis