Audio Issues

I'm not sure if this is a common issue with Win7 or its User--> :) but when I visit various video websites, ie YouTube, news media, the audio varies a great deal. I adjust the sound settings on my task bar, but seem to be doing this more often.

Is there a suggested checklist I should follow?

SysInfo:

Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 7 Home Premium, Service Pack 1, 64 bit
Processor: Pentium(R) Dual-Core CPU E6500 @ 2.93GHz, Intel64 Family 6 Model 23 Stepping 10
Processor Count: 2
RAM: 3036 Mb
Graphics Card: Intel(R) G41 Express Chipset, 1294 Mb
Hard Drives: C: Total - 238315 MB, Free - 87013 MB;
Motherboard: Dell Inc., 07N90W
Antivirus: Avira Antivirus, Updated and Enabled