Please be patient. This isn't like a chat room where responses are almost immediate. Here we can be busy with other things, or offline doing normal life things (like chores, eating, sleeping,...), researching the problem to try to find the best answers (especially if initial suggestions don't work), and so forth. "Bumping" the thread will not help. If you expect a reply from me and I haven't responded in 3 days, then send me a Private Message to remind me - otherwise please hang tight and await a reply. Someone (probably but not necessarily me) will get to you as soon as possible.
System Restore is automatically set to show only 5 days of restore points UNLESS you check the box in the lower left hand corner that says essentially "show more than 5 days worth of restore points." When checked, you will see all that are available and perhaps one will be old enough to suit our needs. See below for a screenshot of what I'm talking about.
If you input the proper product information (which you didn't provide me), here: Support and Service | Dynex Products
they may be able to assist you with updated drivers, firmware, and/or software (check for anything available). If none come up, call them (numbers on same page) to ask where they can be obtained.
Have you tried the headphones on another computer to verify that they work there? If you have the same problem on a different computer, there's a good chance you have a hardware problem with the headset (or just the microphone part if it can be separated).
I don't suppose you know anyone with a spare microphone that you know works that you can plug into your computer to see if it works or if it has the same problem. If it works, chances are good the problem is your headset/microphone. If it doesn't work, then we'll have to look deeper into the problem as it is then most likely something with the computer.
The last two steps are important as they narrow down the problem considerably and tell us where to focus our attention. If you can do either or both, that would be a great help.
I hope this helps.