Not able to go forward after new firmware

I wonder if someone could help me.

I have two 8GB SansaclipPlus mp3 players which I’ve had from new and I use them all the time to listen to audio books, radio comedy things like that as well as music.

After I updated to the firmware ending in .18 recently I found I was unable to move forward or back a track by clicking left or right like I used to be able to.

I haven’t altered anything else and the buttons still work as they move everything else except the track numbers.

This used to work previously, I could just short click and it would jump to the next track…

I downgraded to the firmware before, no change, I downgraded to the one ending 09.  No change. 

It means that I can no longer jump foward or back over a track if I wish to unless I hold the button down to fast forward in stop mode and then it jumps several very fast, obviously.  

Could anyone tell me what has happened and what I can do to get my beloved mp3 players so that if I don’t want to listen to a track I just need to click on to the next one.

I would be very grateful for any information, I realise it is probably something really small that has reset itself that I didn’t know the setting of and had never touched before.