1 Pixel density: Pixel density-The pixel density of a display represents the number of pixels over an area of one inch. 2  Itâs measured in âpixels per inchâ, or ppi.
Eustachian Tube Dysfunction can be caused by large adenoids, allergies, or a cold. This dysfunction can cause crackling or popping noises in our ears. The tube is lined with moist mucosa, and inflamed Eustachian tubes often get sticky, which causes the crackling and popping noises when the tubes are moving around. If the inflammation is serious, it can be easily treated with steroid nasal sprays.
Tinnitus, or ringing in the ears, caused by loud noise exposure is clearly linked to hearing damage, she said. People with permanent ringing in the ears may be able to hear the same volumes of sound as before the damage, but often have trouble separating speech sounds out of a mix of noises.