One or more of the following seems to be true for me:

1. Pads are getting thicker, so they tend to rub more.

2. Makers are using coarser threads to sew the chamois on.

3. My older skin is more sensitive down there.

I'll hit the front and sides of my chamois with Body Glide or chamois cream before I put them on. That seems to take care of all three. But do be sure to pull the shorts up snug before you start riding.