Turn the volume down - one thing I've noted with SDR# is if you push the volume slider to 90%+ it'll really screw up the resulting audio output, either distorting it madly or just clipping it so extensively what you end up getting is nothing at all. It depends, of course, on what you're attempting to monitor but in my experience I realized that I was getting some bad decodes on some digital content passed to DSD+ because I had the volume level set so high. Try setting it about 50% and work from there.
I don't see anything in that screenshot that jumps out as a problem save for the signal you're receiving is pretty excessively strong - that overload of signal + the volume set so high could just be killing it, and probably is, but then again maybe not.
Realize that the "cheap USB TV tuner" RTL sticks - if that's what you're actually using and it seems like you are - happen to be very susceptible to signal overload conditions, especially if the gain is set high. You didn't comment on that so I'm going to presume you have the gain enabled to some degree, with the RTL AGC and Tuner AGC
off (their selection boxes are empty/unchecked) and just using the slider to adjust the gain manually (I mentioned 32 dB earlier - actually 32.8 dB on SDR#'s slider - so give that a shot to start with).
If you're using something like a CB radio or a 10-meter Ham radio and keying up the mic of the unit in close proximity of the RTL stick/antenna you're basically killing it with signal as that screenshot clearly shows which will cause it to clip so bad you're not going to hear much of anything but static and distortion (if you even hear that). It's pretty obvious from the IF Spectrum along the bottom of your screenshot that the signal is peaking above 0 dB so yeah, way way too much.
Honestly here's my suggestion: start with a clean "install" of SDR# just for testing, with zero plugins added meaning only use the plugins that come with SDR# by default - I see you've got quite a few of them installed with that one from the screenshot so, in troubleshooting situations you reduce everything to the bare minimum and start with something that works and add components till something breaks.
You can easily do this with the SDR# archive by just extracting the contents to some other location, another directory/folder with another name like sdrsharp_test or something, and then install the RTL SDR dll files using the batch file after which you can then fire it up and do testing with basically everything at the raw defaults (adjust the gain and ppm as needed, however, but not much if anything else) and see where you get.
