just got a Nokia 5300. problem is when i use the 2.5mm to 3.5mm adapter(that came in the box)to listen to music on my Philips HP800 headphones, there's a continuous disturbance in the background, a kind of hissing noise. problem isnt with the headphones coz the sound comes when i use my Sennheiser headphones too. and there is no problem when i use the Nokia headset which directly plugs into the 2.5mm jack. so problem is definitely with the adapter. Can i get a better adapter for the phone?