DO NOT DABBLE IN HYPNOTHERAPY
either consult a trained hypnotherapist or do not use it. "it opened up my mind to some other similar ideas" is an obvious sign that you did not do the process correctly.
There are many methods to extinguish phobias (any of them). The one that uses sound is EMDR. However, the sound is not to relax, it is to reprogramme.
hypnotherapist has many tools to extinguish phobias. The most useful is systematic desensitization.
EFT/TFT is also useful. Look it up on youtube.
a simple yet effective tool is thought stopping. I have used it many times successfully. It works like this:
On exposure, feel the fear yet do nothing. Do not change breathing etc.
count to ten
Then mentally (if in public) out loud (if in private) shout 'STOP'
then take a long slow breath, focusing on the air filling you.
hold the full breath for a count of 4
then mentally (if in public) out loud (if in private) sigh on the out breath 'calm'
hold the empty breath for a count of 4
Continue for about ten breaths
Now you may feel light headed before ten, if so, stop there.
By using this WILL extinguish any phobia because it turns off the fight/flight response (which is the bodily process of all fears/phobias)
30 years counsellor / 15 years hypnotherapist.