Cat suddenly afraid of drinking fountain

I felt like spending some money, so I bought a Drinkwell Pet Fountain
the weekend before last. I washed it and set it up and Cat was very
interested and cautiously investigated it and was soon drinking out of
it contentedly.

For the next week, she seemed quite comfortable with her new source of
water, hardly touching her old water dish at all.

Last weekend, I decided to get the "Aqua Garden" accessory for it.
(This is a little attachment which holds wheat grass seeds, which are
supposed to sprout into wheat grass).

Before putting that in, I washed the whole thing as I had initially done
and put it back where it belongs. As soon as it was on the floor, she
was curiously checking out the reservoir/filter area as I hadn't even
put the top back on yet. I had to move her out of the way to replace
that and then I sat down to open up the Aqua Garden and install it which
only took a few minutes, by which time Cat moved on to other Cat
activities. She didn't use it after that I noticed and seemed to be be
walking cautiously whenever she went passed it - I though maybe she was
just being strange and didn't associate her behaviour with the fountain
at all until the next day when she kept doing it and when I moved her
from my lap to a spot next to the fountain, it was obvious she was
afraid of the thing now.

She still seemed curious about it and cautiously approached it, but
wouldn't get close enough to touch it. I turned the water-flow down,
then removed the "Aqua Garden" and finally just unplugged it altogether.

She eventually worked her way up to actually drinking a little from it,
but still seems very wary of it.

I just changed all the water out of it in case there was some remnant of
"Aqua Garden" smell that was bothering her. While I was doing this, I
set the Aqua Garden on the counter to test her reaction to it. Somewhat
cautiously (but not nearly as cautious as she was towards the fountain),
she moved it around on the counter with her paw and I took it back so
she wouldn't knock it to the floor.

After changing the water, she cautiously approached and nudged the cord,
but didn't drink or even sniff at the water.

Just wondering if anyone has experiences with these things or any idea
on what's spooked her. I don't believe it gave her a shock as I believe
I would have noticed her reaction since I was quite near the fountain
from the time I washed it to the time she seemed to become wary about it.

I've contacted Drinkwell's customer service with a similar version of
this post to see what they have to say.