ac adapter hissing noise

Hi, I got a new ac adapter and cord about a year ago for my hp pavilion. My last one had a tear, so i bought one over ebay. The adapter worked fine so far, though it does seem to overheat more easily. Recently, when it overheats, the adapter has made a loud hissing noise. This has happened maybe twice already. Is this a result of the heat? Is it normal or is it broken? Should I get a new one? I'm traveling abroad in a few days so I want to solve this issue, but buying a new one from stores would be pretty expensive. Thanks for any input

Hi, I strongly recommend you take it out of service IMMEDIATELY……This is not normal and could indicate a dangerous problem. Either renew it or have it checked by a competent electrician……but please don't use it until it has been checked out……(Potential Fire/shock risk etc) If you take it out of service then please render it inoperable or tape to it a large and unmissable label that it should not be used and is potentially dangerous. If the electrician condemns it ,then ask her/him to destroy it ,or destroy it yourself so that a stranger would not be at risk by unwittingly plugging it in. This may seem like excessive precautions……………………..but we do like to keep our members and their family and friends alive if possible! Regards paws