Why for the life of me I can’t stay awake when listening to Music?

This happens to me all the time too. I don't think it's a bad sounding system, but rather a good one. The funny thing with me is I always wake up as soon as the music ends. Not between songs, but when the CD or playlist ends. This does not happen with LPs as there is not enough time to even fall asleep before I have to turn over the LP. I love when this happens as my listening sessions are to relax anyway. When I'm listening to music I usually have nothing else going on.

@koestner I am glad to hear that I am not the only one. True my system keeps me relaxed and funny thing is that I start enjoying the cat nap while listening to some jazz lol. I sold all my vinyl albums and gear which was the big mistake I did because definitely I stayed awake to not ruin my stylus or records. Maybe I need to start all over but it is too expensive now.

Yeah, we can call that a "Cool Cat Nap"

   As we age our bodies change , usually not for the better. At 68 I’m struggling with getting sleep. I have a modest headphone system on my nightstand and play music Vs trying to use the living room system. FWIT back in the day I had a 240 gallon aquarium in the living room. I’d turn off all the lights except for the tank and play an album and watch the fish to relax. Wherever you are in life enjoy the day as it will be gone. Best wishes , Mike B. 

Your brain may have become wired for different kinds of stimuli than music alone. It's common these days with so many options out there - most of them far less healthy than a good music session. If these sessions are important to you: either combine activities (like reading / social media), move sessions to earlier in the day, and/or re-examine your overall habits including substance intake which might make music alone seem a little under-stimulating.