Add a 1- or 2-frame audio dissolve. You can make them even shorter if you change the sequence to show Audio Time Units; click the pancakes menu on the upper right corner of the Timeline panel and select it there.
I would look closely at the edits. Not editing on Zero Crossings can introduce clicks and pops. This ARTICLE goes into more detail.
One feature that I wish PrPro would add is the Cut on Zero Crossings, from Adobe Audition.
Thanks, Colin and Bill. The transition worked.
Nice article Bill. Yes, would be nice to have that feature in the NLE.