I'm curious if brass is typically susceptible to this kind of thing. Thanks!
Brass is not an especially hard alloy. For comparison brass (depending on the exact composition) has a Brinell hardness of around 100, lead about 30 and tool steel 600+.
if the mark is bugging you even a little , I've found Mike is quick to reply through their website's messaging feature. I'd just mention the issue and ask if they could send out a fresh one.
As mentioned above, I also rolled the pre-amp back a bit. I have a hunch it was set to the +10dB that the Dozin page indicates the original had.
Now I have to cycle through all my DIY effects to figure out which work best... Mrs. C is already tired of hearing the Estimated intro just dialing in the DIY Snow White.