You have had noise-induced tinnitus for many years. This type tinnitus will usually remain stable once habituation has been achieved but recently it has become problematic. I have mentioned reasons for this in my post: Will My Tinnitus Get Worse? Please read it as it refers to people that have noise-induced tinnitus.
I have looked at some of your early posts to this forum, as this can give an indication of what might have caused the increase in the tinnitus, how it is affecting you and so see what treatment you have tried and whether you have been seen at ENT? You have been given some good advice and support by some forum members, so please accept my apologies if I happen to mention some of them again.
The most common cause for a resurgence in noise-induced tinnitus after a long habituation period such as yours, is listening to music through any type of headphones even at low volume. Listening to loud music through speakers or being exposed to other types of noise trauma. This could be work related or a hobby such as firing a gun on a shooting range. If you have participated in any of the things I have mentioned, their effect would have taken some time to reach full manifestation and therefore, would probably go unnoticed for quite some time because of your long habituation period. This happens and is particularly relevant to people that have noise-induced tinnitus.
Another indication of noise being the cause of the tinnitus increase is experiencing spikes, which usually means, noise trauma to the auditory system that has made it oversensitive to sound.
If noise isn't the cause there are other things to consider. Some people with tinnitus are adversely affected by aerobic exercises. Running on hard ground or treadmill due to impact underfoot. It travels up through the feet, legs into the upper body head and auditory system and can cause spikes. Some people find lifting weights can affect tinnitus too. Stress can also make tinnitus worse but as you're a veteran, you have probably learnt to manage this quite well over the years.
If none of the above resonate with you then you could have developed an underlying medical problem within your auditory system, as I note that you have been experiencing dizziness and vertigo? I see you have been examined at ENT, so if there was anything untoward going on I would have thought it would show up in tests. However, if you are still experiencing this perhaps it would be a good idea to get a second opinion. I also see that you have ETD issues? As you know that can cause problems with tinnitus and really needs the intervention of an ENT doctor for treatment.
You have mentioned noticing an increase in the tinnitus after the COVID-19 vaccination. This could also be a factor and should be investigated after the other things I have mentioned have been ruled out as the cause for tinnitus increase.
I suggest that you see another ENT doctor for a full examination including hearing test, ETD and MRI. If you are given the all clear, then you should be referred to Audiology and see an Audiologist that specialises in Tinnitus and Hyperacusis treatment and management. Treatment can involve: counselling, medication, sound therapy or a combination of all three. This is the right health professional for you to see, once your ENT doctor has decided there is no underlying medical problem responsible for the increase in tinnitus or spikes.
Continue using low level sound enrichment something that's soothing. Please remember not to overprotect your ears. Read my post: Hyperacusis, As I See It.
I wish you well.
Michael
Will My Tinnitus Get Worse? | Tinnitus Talk Support Forum
Hyperacusis, As I See It | Tinnitus Talk Support Forum