Light Flashing or Funny Dial Tone
If you have a device that supports Message Waiting Indication (MWI), it will do one or all of the above things when you have a new message.
Check your manual to see how to switch this function off and on.
You can clear your messages by dialling 1571, viewing your voicemail in the Control Panel and deleting them or calling them from your phone.
You may need to have the latest firmware installed - please check the manufacturer's web site. Some adapters do a regular, partial ring when they have a message waiting.
To turn this off you may need to consult your manual.
For Sipura's, you will find it under 'User 1', 'Ring Settings'.
Change any number in the 'VMWI ring splash length' box to 0.