[B. W.]

At 24 seconds in it starts to load up (too rich). Depending on ambient temp you may want to roll back your choke a little (the black round plate on the side) It also sounds like your fast idle is a little low (a higher fast idle will help prevent load up) Those noises did sound like backfires - a backfire is almost always ignition related, most fuel related backfires are when it is runnig very lean or very rich so check/adjust your mixture screws. (it's not popping at fast idle but it is at idle) also confirm timing, check ignition components (plugs, wires, cap, rotor) A cold engine requires more KV to light the mix so with worn parts it may run fine when warm but have a miss/stumble when cold.
Lets say, for sake of argument, that your mixture screws are almost all the way in (lean), your choke is dialed too rich, your plug wires are worn & cross-firing - You are dealing with three separate issues, don't expect one adjustment to fix everything. If it were me, I'd re-check my ignition system, if a part is suspect, replace it, adjust the carb using edelbrock's manual, set timing & go from there.