They sound pretty much like a linear MX with some sand inside, it's scratchy (not saying it's good or bad, but it's scratchy, it sounds like there is some very thin sand inside)
Interestingly, the spring is also much cooler in color, it looks sand-blasted
Overall an interesting switch, I bought tactile greys, received linear greys, tactile greys also have the same scratchy sound
It sounds like rub+rub+rub (you can hear the plastic+plastic scratching)
When you push and suddenly release the switch, there is also a very audible spring ping, but it's probably not on a very bad frequency, it's very short lived but audible
