If I may be so bold to suggest, FIRST start and get yourself a piece of paper and a pen/pencil, or if you have no paper and have a digital camera, use that.
And then write down on paper the name of tools and items you try. Take a pix with a digital camera if necessary (or even a screen dump with the app name showing). You need to do something to help your memory. I type that as a person who has a really really REALLY bad memory, and these are tools that are indispensable for me. Stating you have done something you can’t remember the name of is not much help to those trying to help. Apologies for my stating that, but its really important to remember else everything will be chaos .
Did you try installing the application pulse audio volume control (pavucontrol) ? If not install pavucontrol if not already installed, and use it to tune your audio, running pavucontrol each time (the first time) you run a multimedia application. Be certain in the Configuration Tab to select the correct device. Be certain in the OUTPUT tab to select SHOW all output devices and that your audio is not muted, and be certain in the PLAYBACK tab (which will be populated correctly only when trying to play audio) to have show selected to ‘show all streams’ and that you have the correct output device selected for the application with the volume at appropriate levels.