I've experienced similar difficulty listening to other people. I also suffer from PTSD from childhood trauma. I have a general issue trusting other people and can tense up even around the most chill, kind, gentle people. I think you're right, it is related to the PTSD and you've got this cycle of fear and avoidance when it comes to listening to other people speak. It's like a barrier between you and healthy, human connection. It's craving that connection that's making you ask for help and the best way to help yourself is patience, self-compassion and therapy. Therapy slowly turned down the background noise for me, took my baseline level of trepidation and turned it way down, so I'm not on pins and needles when I'm talking with or meeting new people, when I'm in a crowded place, or when I'm full of anticipation. I'm not 100 percent. It's a work in progress, but I'm way better off than I was 9-10 years ago. I could hardly even recognize the old me. Hope this is helpful