I had brake problems with my 4100 when it was new, similar to what you describe.
Maybe the same, maybe not. Originally the parking brake seemed like it wasn't releasing correctly and eventually plenty of brake noise. External brake linkage adjustments were all correct.
My dealer advised me to contact Deere's Customer Communications Center 1-800-527-8233 and after no improvement following a suggested change of fluid and recommended treatment with a JD supplied oil additive called PEMO (a fluid friction modifier designed to reduce excessive brake noise), my internal brake components plates, friction discs etc. were all replaced under warranty service.
I understand there are service information bulletins out on using Pemo. According to the label its been called out for use on the 655, 755, 855, 955, 670, 770, 870, 970, 1070, 790, 990, 4500, 4600, 4700, and now for the 4100 also.
Here's a link to my original posting
<A target="_blank" HREF=http://www.tractorbynet.com/cgi-bin/compact/showflat.pl?Cat=&Board=ag&Number=47323&page=1&view=collapsed&sb=5&o=0&fpart=>http://www.tractorbynet.com/cgi-bin/compact/showflat.pl?Cat=&Board=ag&Number=47323&page=1&view=collapsed&sb=5&o=0&fpart=</A>
DFB