A)Hello. Thanks for writing to us.
Hearing impairment is the most common finding in association with cold and it is temporary. It could also be because of various other reasons like ear wax, Foreign body, infection in the middle ear leading to collection of pus, or fluid, infection in the inner ear or it can also be swelling in the inner portion of the auditory tube. The inner part of auditory tube is in conjunction with upper part of throat. Thus it gets affected during the episodes of cold. This causes it to block the normal resonance leading to difficulty in hearing. There can also be other causes like the use of drugs that cause damage to the hearing apparatus, sensorineural impairment, which can be distinguished by the duration of symptoms where sensorineural hearing loss is for a longer duration.
Bell ringing sensation in your ear on & off is nothing but tinnitus. It can also occur in the above mentioned conditions. In both the conditions, the affected ear should be examined, history should be taken and all other medical disorders should be ruled out. I would like to recommend you to consult a ENT specialist for further management of your case.
Hope this helps.