Occasional Clicking Sound (Blinker sound) coming from instrument cluster

[Mike87]

On occasion, 1 in 4 or 5 times, I open my door (87) to go to work in the morning and immediately hear this clicking sound coming from the dash behind steering wheel. The sound is like that of a blinker sound or an emergency flasher sound except slightly faster. It starts fine etc. but feel it may be draining my battery a little as start lights always seem a little dimmer when this happens. When I leave the car this noise is not present. The sound kicks in after I leave. I suppose it goes on all night sometimes. Any ideas what this might be? Thanks.

87 Turbo, automatic