Had it years ago when I worked in Bratislava. Absolutely murder, was sitting in a hotel room with my ipod cranked to 11 and still could barely hear a thing. Eventually went to a Slovak doctor who got it syringed. Instant relief! The amount of gunk that came out was unreal
Had it again here last year but now they don't recommend syringing due to the potential to damage the sensitive parts of the ear. So it has to be Otex ear drops, which do the job but you just have to be patient, it can take a few days of drops going in to clear it...