Loud noise exposure: Being exposed to occupational loud noise on a regular basis from heavy equipment, chain saws or firearms is a common cause of tinnitus. However, even if you don’t work in a noisy environment, you can still suffer the effects of noise exposure by listening to loud music through headphones, attending live music performances frequently and engaging in noisy hobbies.
When tinnitus is unexpected and unwelcomed, it can lead to a negative reaction to the tinnitus. This can create a vicious cycle. When tinnitus is perceived, it can prompt emotions, including frustration, fear, unhappiness, etc.  These can, in turn, cause physical reactions such as anxiety and stress.  This reinforces the tinnitus and perpetuates the cycle. 
Subjective tinnitus is the most frequent type of tinnitus. It can have many possible causes, but most commonly it results from hearing loss. When the tinnitus is caused by disorders of the inner ear or auditory nerve it is called otic (from the Greek word for ear).[25] These otological or neurological conditions include those triggered by infections or drugs.[26] A frequent cause is noise exposure that damages hair cells in the inner ear.
Spontaneous otoacoustic emissions (SOAEs), which are faint high-frequency tones that are produced in the inner ear and can be measured in the ear canal with a sensitive microphone, may also cause tinnitus.[6] About 8% of those with SOAEs and tinnitus have SOAE-linked tinnitus,[need quotation to verify] while the percentage of all cases of tinnitus caused by SOAEs is estimated at about 4%.[6]
One of the big problems associated with curing tinnitus, experts say, is that it’s really a symptom of multiple conditions, as opposed to being a single condition with a predictable trigger. In fact, more than 200 different conditions — problems ranging from hearing loss to head or neck trauma — have been linked with tinnitus, which makes it a real bear to try to stop. (3)
The diagnosis of tinnitus is usually based on the person's description.[3] A number of questionnaires exist that may help to assess how much tinnitus is interfering with a person's life.[3] The diagnosis is commonly supported by an audiogram and a neurological examination.[1][3] If certain problems are found, medical imaging, such as with MRI, may be performed.[3] Other tests are suitable when tinnitus occurs with the same rhythm as the heartbeat.[3] Rarely, the sound may be heard by someone else using a stethoscope, in which case it is known as objective tinnitus.[3] Spontaneous otoacoustic emissions, which are sounds produced normally by the inner ear, may also occasionally result in tinnitus.[6]

A brain tumor can be either non-cancerous (benign) or cancerous (malignant), primary, or secondary. Common symptoms of a primary brain tumor are headaches, seizures, memory problems, personality changes, and nausea and vomiting. Causes and risk factors include age, gender, family history, and exposure to chemicals. Treatment is depends upon the tumor type, grade, and location.

Millions of Americans experience tinnitus, often to a debilitating degree, making it one of the most common health conditions in the country. The U.S. Centers for Disease Control estimates that nearly 15% of the general public — over 50 million Americans — experience some form of tinnitus. Roughly 20 million people struggle with burdensome chronic tinnitus, while 2 million have extreme and debilitating cases.1