Factory Textures don't make sound

I can’t tell where they are supposed to exist. Imported textures work just fine but none of the factory textures.
where are they kept?

Check your audio I/O prefs page.
If Envy sees 3, 4, 5 output channels (or more) it assumes you’re using a surround layout and it sends Monos to the C and stereos to the L/R.
If you don’t have those audio channels playing out a speaker then you won’t hear them.

NOTE: you might need to make the I/O changes - then restart Envy for them to fully take effect.

this worked THanks so much for your support!