Suddenly the driver's side door makes an annoying pop-pop sound when opening and something (hard to pinpoint) seems wrong with the hinge.

At the same time (not sure if related), the driver door speaker stopped functioning.

Haven't yet removed the interior door panel to check on the speaker (pouring rain as we speak).

Something broke and interfering?

Your door has fatigued at the connection with the door stop. Very common. And also not a lot that the shade-tree mechanic can do to fix it.
See a body shop. They can probably tack-weld the skin back together.

It can be reinforced and 2 bolts added to make it better. No welding required. See my post.

Klaus
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1967 220 belonging to C.A. lives on

I stand corrected! Well done.

The PO of my '95 had a body shop weld the passenger door. I didn't realize it was so easy to fix with just bolts. This is good - I have to do the driver's door.

You can take a small piece of steel to slip in behind, just make sure the bolt holes match, to help reinforce the sheet metal.

After you are done, grease the door stop strap with lithium grease. This is why they fail so often, no one ever greases up the sliding/turning bits.

Have fun!

Klaus
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1967 220 belonging to C.A. lives on

You could also use thick aluminum washers on the back side and nuts with the plastic insert so they never loosen??? Just trying to improve the process.

Klaus
--
1967 220 belonging to C.A. lives on

I did mine last week by drilling & tapping. Used a stainless 5/16 - 18 cap screw and Loctite. So far OK.

I found this on the web a long time ago. Try copying it to your PC if you can. If you cannot see the pics, let me know.

http://web.archive.org/web/20060426164605/http://au.geocities.com/ozbrick850/door-stay_fix.html

OzBrick had a great site.

Klaus
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1967 220 belonging to C.A. lives on