Hey Justin! I just started your course and I have tried to perfect D chord and the 3rd and 2nd Finger Parts are Buzzing and I can't do it! Can you give me a couple Ideas?
I am no expert, just beginning too, but I have had trouble with the 2nd finger being too far onto the fret when I try to get the 1st and 3rd fingers forward near their frets. I have been trying to give myself a little more leeway to place the 1st and 3rd a little further back to free up room for the 2nd.
Play with your finger location between the frets and see where you can place them and still have good sound. Then find and learn the spots where you can get all three to ring true.
I found that my guitar, bought used with super long lasting phosphor bronze strings was NOT forgiving at all and I either had to crank really hard or be extremely precise, and being a beginner, I had sensitive fingers and not enough flexibility to manage very well (still the case...). I took the guitar in to be looked at and it is a good guitar, so I put softer, more flexible strings on (silk and steel for me). World of difference. It takes less pressure and opens up the usable string between the frets more.
Also, I seem to have trouble with my 3rd finger moving too slowly to get the the d string in a timely way. I am now trying to relearn the D cord by placing my fingers in the 1-3-2 order. Already going faster, but it backed me up a bit.
Keep trying!