Bad Wiper Motor?

Hello, new to this site, but have gotten some great info from reading so far.
But I've got a problem I need to ask about. My wife's 2008 Prius starting making a mechanical weird noise when you turned on the wipers. The faster the wipers went the faster the noise was (not really a grinding or popping, just an odd robotic mechanical noise). This has been a while back, and then the noise went away. But then I noticed the wipers were slower, and it doesn't matter what setting they're on (even though they still work) they are just one SLOW speed now.

So, I'm assuming my wiper motor has went bad. Just wondering if anyone else has experienced this and could let me know what they had found before I order a motor and try to replace it.
Thanks!