Brief Answer:
yes it certainly can..

Detailed Answer:
Hello XXXX, Welcome to HCM,
I've gone through your query and understand your concern,

The answer for your query is yes, impacted wax deep inside the ear canal can cause light headedness (as it interferes with the balance equilibrium of the mid-inner ear).. So, if suspected, it's strongly advised to get yourself examined by an ENT specialist for a through cleaning of it under direct vision..

However you should also note that certain other metabolic disturbances, any irregularity of the blood pressure, drop in hemoglobin(anemia), irregular heart rates(arrythmia), a repeat check-up of your disc problem(by your neurologist) should also be considered for further evaluation in this regard (if not done already)..

Let me know if there's any further queries..

Take Care
Kind Regards

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