My Tinnitus is coupled to poor sleep (both quality & quantity) and I noticed an improvement on that front as well after a few days of magnesium.
I started taking L-Theanine in the form of matcha tea together with my girlfriend. Since then we're both experiencing vivid dreams. Unfortunately we've also started taking this at the same time before bed: https://www.physalishealth.com/en/food-supplements/stress-sl... ... so we're not quite sure which one is improving the vivid dreams.
I started taking magnesium several weeks before I started with the tea and the relax & sleep supplements. It was because of the apparent success with magnesium that I'm now exploring these paths. I'm not sure whether Taurine has any effect (the supplement I started after Magnesium and before L-theanine). I'm sticking to the Glutamine-Glutamate-Gaba model and found this site that has a number of pointers and supplements in that area: https://bebrainfit.com/glutamate-neurotransmitter/
I'd advise to try one at a time, around the same time every day and evaluate after a week. Start with Magnesium (not in the form of an oxide)