After the Minecraft launcher updated to the newest version a few days ago, I tried to play Minecraft 1.7.2. However, when it loaded up, none of the sounds were working. It was completely silent even though I had all of the sound options turned up to maximum. Upon further searching I found that the default resource pack had a red text next to it saying: "Missing pack.mcmeta " I loaded up a few other older versions of Minecraft and found that this problem was only present in the versions earlier than (but not including) 1.7.3.

There was a similar issue posted back in 2013 on this website that was titled: "Default resourcepack says 'Missing pack.mcmeta'" with much the same problem. While it said that the issue had been resolved, I could not find any indication of the method used to fix the issue.