My slow close toilet seat now slams shut. Are there any adjustments I can make to correct this problem?

WOW! Slow-close toilet seats. What will "they" think of next, to pick your pocket?

Slow-open mechanisms such as cassette players and top-loading DVD players use a special type of grease to achieve that effect.

The screen on the laptops uses a friction mechanism based on a "clutch-spring" with enough holding power to keep the display in the position selected.
This "clutch-spring" is factory adjusted so it neither slips under the weight of the laptop screen, nor is so tight that extra force is required to close the laptop.
These things do wear out, and as a rule are not user serviceable.

Can you adjust it? Good question!
Can you adjust it so it works? Ahah!
My rule of thumb: If it's already broken, how much more broken can it get?

Therefore, my conclusion is that the toilet seat's slow-close mechanism is factory set at the point where it will neither slam down nor stop half-way, but glide down gently until it's closed.

An interesting added feature would be for the toilet to recognise who's about to use it, and for what, select the seat position be it up or down, and then regulate the water volume needed to flush.
Also, it could flush itself once the lid is fully closed, to avoid or minimize the dreaded "toilet flush mist". arrrghhh!!!

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