Has my 54 plate Octavia for 2 years. During that time the lock and unlock on the button has worked fine with the flashing of indicators. Today, just on unlock, there is a quiet beep. Nothing sounds on locking.

Any ideas please?

Well, as a beep can be turned on for lock and unlock somehow it must have been turned on. Someone with Vag-com or a dealer should be able to turn them on or off in 5 minutes. It's simple to do.

i agree with roo here, unless the car has decided to change codes on its own.

If you have got the maxidot display you can change it back to silent yourself, otherwise as mentioned above you need vagcom or a dealer.

not all maxi dots will allow you to, have a look in the vag com section for someone living close to you and send them a pm asking if they mind.

..... unless the car has decided to change codes on its own.

I think this is entirely possible. Mine has turned its confirmation beep on several times without intervention - I just turn it off again with my maxidot.