Are you sure your default audio device is what you think it is? Go to Control Panel -> Manage Audio Devices.If you run Windows 10 spring creators update, make sure you do not have disabled mic and webcam access in the privacy settings as they might run from same device.Look at options to disable it at startup and set the output to DirectSound (no wasapi). If you see 'Error: Failed to initialize audio.' then you have a program on your PC that has exclusive control of the audio (Nahamic, Sonic, etc.) and you need to disable that program before any Rainmeter visualizer will work.If you have it low then push the volume up (higher than 50%) and see if your visualizer starts to react.

Check the volume mixer setting and see if master sound is not set to a low volume. The bars might not react with a low volume level of master.Check this example skin to be sure the problem is not on a skin level: Example Audio Level Spectrum.rmskin.Disable your antivirus, restart Rainmeter and see if that made any change. software interferes with Rainmeter or sound drivers.

It is useful to check if your antivirus/antimalware/etc.

If nothing helps at the end of the post it is described how to get helpful information of your problem before making a post on the forum. Before posting your problem on the forum make sure you go through this troubleshooting guide.

Rain meters