Pop heard when stylus dropped into lead-in groove

Ditto. In fact I keep my phono stage on mute because I don't want the transient pop/thump to be amplified in the phono stage circuitry.

BTW, I also notice that on some records, the first couple of rows of groves sound like the stylus is dragging its butt or something like that. But even in such cases, everything smooths out after the stylus tracks a couple of rows of grooves. I also double checked VTA, azimuth, alignment and VTF. Everything seems ok. Something to get used to I suppose??

Ah. To mute or not to mute, that is the question...

I, too, am an unmuter. I like to know where my tips going.
I have friends that mute like there's no tomorrow. I just dont see the need.
Now if several are cueing during the same listening session,
It could be wise to mute for various unbeknownst volume settings.

The loud pop comes from the high forces deflecting the cantilever when the stylus is dropped into the groove. It is exacerbated by a number of factors. First, one must cue the down the arm slowly to minimize this force. The pop can become more of a problem if the cuing rate has changed (most cuing devices use viscous dampening and the tendency is for the drop rate to increase as the mechanism ages). If your arm does not allow for an adjustment to the drop rate, you will have to lower the rate yourself by slowly moving the lever each time you cue.

Sometimes the rubberize bar that holds the arm in place becomes less tacky which allows the arm to drift out of line when it cues down. If your arm provides antiskating, this causes the arm to drift outward toward the edge. If the arm cues too far out toward the edge of the record, the stylus will land on the high edge bead. The arm/stylus will then fall downward to the lowspot inside of the bead; this fall and abrupt stop is often the cause of a loud pop. Try cuing the stylus further into the record to avoid hitting the outer bead.

Slower cuing and cuing far enough into the record to avoid the outer bead is usually enough to minimize any sort of loud pop.

I discovered the culprit. I had the gain set on my phono stage (Aesthetix Rhea) to the highest setting (75). I don't remember going there, but perhaps I was experimenting and forgot to return it to where I normally have it set (62). I also had my VTF tracking at the high end of the recommended range, so I scaled that back slightly as well. The combination worked to amplify what we all hear as normal to the point where it sounded like a static charged particle. I still hear it, but it no longer draws attention to itself. Its nice to "fix" things for free.