Most tinnitus is "sensorineural," meaning that it's due to hearing loss at the cochlea or cochlear nerve level. But tinnitus may originate in other places. Our bodies normally produce sounds (called somatic sounds) that we usually don't notice because we are listening to external sounds. Anything that blocks normal hearing can bring somatic sounds to our attention. For example, you may get head noise when earwax blocks the outer ear.
The accepted definition of chronic tinnitus, as compared to normal ear noise experience, is five minutes of ear noise occurring at least twice a week.[50] However, people with chronic tinnitus often experience the noise more frequently than this and can experience it continuously or regularly, such as during the night when there is less environmental noise to mask the sound.
Medication. Some medications are known to be ototoxic while others list tinnitus as a side effect without causing permanent damage to the ear structures. New medications come out so often that it is difficult to maintain an up to date listing; another option, if you are experiencing tinnitus and are curious if it could be your medication, is to talk to your pharmacist or look up your specific prescriptions online through a website such as www.drugs.com. You should never stop a medication without consulting with your physician, even if you think it may be contributing to your tinnitus.
In some cases, a special audiologic device, which is worn like a hearing aid, may be prescribed. These devices, called masking agents, emit continuous, low-level white noises that suppress the tinnitus sounds. In some cases, a hearing aid may be recommended to help to suppress or diminish the sounds associated with tinnitus. A combination device (masker plus hearing aid) may also be used. Masking devices provide immediate relief by reducing or completely drowning out the tinnitus sound. However, when the masking device is removed, the tinnitus sound remains.
Tinnitus is a common condition characterized by the perception or sensation of sound even though there is no identifiable external source for the sound. Tinnitus is often referred to as a “ringing in the ears.” However, the sounds associated with tinnitus have also been described as hissing, chirping, crickets, whooshing, or roaring sounds, amongst others, that can affect one or both ears. Tinnitus is generally broken down into two types: subjective and objective. Subjective tinnitus is very common and is defined as a sound that is audible only to the person with tinnitus. Subjective tinnitus is a purely electrochemical phenomenon and cannot be heard by an outside observer no matter how hard they try. Objective tinnitus, which is far less common, is defined as a sound that arises from an “objective” source, such as mechanical defect or a specific sound source, and can be heard by an outside observer under favorable conditions. The sounds from objective tinnitus occur somewhere within the body and reach the ears by conduction through various body tissues. Objective tinnitus is usually caused by disorders affecting the blood vessels (vascular system) or muscles (muscular system).

It’s been found that exposure to very loud noises can contribute to early hearing loss and ear problems. Loud sounds can include those from heavy machinery or construction equipment (such as sledge hammers, chain saws and firearms). Even gun shots, car accidents, or very loud concerts and events can trigger acute tinnitus, although this should go away within a couple days in some cases. (5)
A wealth of research has gone into understanding the mechanisms of tinnitus due to the increased concern in our ageing and noise exposed society through the support of organizations such as the Tinnitus Research Institute, the American Tinnitus Association and even the US Department of Defense. This research has helped us to understand not only why and how this phantom percept can develop, but also sheds light on why it may sound like a hiss for one person and a high pitched tone for another.7 In addition, neuroscientists have shown connections between the limbic system (where emotions are processed) and the auditory system; it is not uncommon for tinnitus to increase during times of stress or negative emotions.5 As such, the effective tinnitus treatment strategies should be enjoyable and positive, and should account for the variability in what tinnitus sounds like for each patient.
Tinnitus is the perception of sound when no actual external noise or sound is present. It is often referred to as “ringing” in the ears. I have even heard some people call it “head noises.” While ringing sounds are very common, many people will describe the sound they hear as buzzing, hissing, whistling, swooshing, and clicking. In some rare cases, tinnitus patients report hearing music. I hear about 2,000 crickets all going at once! 
Wearable sound generators are small electronic devices that fit in the ear and use a soft, pleasant sound to help mask the tinnitus. Some people want the masking sound to totally cover up their tinnitus, but most prefer a masking level that is just a bit louder than their tinnitus. The masking sound can be a soft “shhhhhhhhhhh,” random tones, or music.

If you’re struggling with tinnitus and experience anxiety or depression relating to your condition, cognitive behavioural therapy is a form of counselling that helps you to cope and readjust your negative feelings. Tinnitus retraining therapy (TRT) can also be used in conjunction with CBT, harnessing the body's natural ability to tune out sounds and make it part of your subconscious mind rather than at the forefront.

When a medication is ototoxic, it has a toxic effect on the ear or its nerve supply. In damaging the ear, these drugs can cause side effects like tinnitus, hearing loss, or a balance disorder. Depending on the medication and dosage, the effects of ototoxic medications can be temporary or permanent. More than 200 prescription and over-the-counter medicines are known to be ototoxic, including the following:

Atherosclerosis. With age and buildup of cholesterol and other deposits, major blood vessels close to your middle and inner ear lose some of their elasticity — the ability to flex or expand slightly with each heartbeat. That causes blood flow to become more forceful, making it easier for your ear to detect the beats. You can generally hear this type of tinnitus in both ears.
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