if your computer, headphones, etc look like used items (i.e. not sealed in brand new packaging) then they won't bother you....

they don't bother with currency as well unless you are carrying huge sums of money....currency changers are available at the airport as well....

in a worse care scenario if they stop you then you have the option of getting a note put in your passport with the serial numbers of the electronic goods....this will allow you to bring in the goods into the country & they will match that to the items on your way out to ensure you are carrying them back...but its extremely unlikely that it would come to this....