For some strange reason the output sound on my phone has gone really low!

Yesterday was fine - was playing Angry Birds - sound quality brilliant.

Today I came to play it and it was really low ( I had not altered the sound in the meantime )

I checked my volume and it was near the top!

I switched off and on - same problem.

Tried my music files - same problem. Not got a clue how this has happended. Was fine when I played Angry Birds last night and I have done nothing since apart from charge it.

I have put my ear to both stereo outlets and sound iscoming from both - it's just that it's really low