buzzing sound when hazard and left turn signal on

[ssiikkssii]

First, sorry for my bad english.

A have a problem with buzzing sound from my turn signal relay when I turn on left turn signal and turn on hazard. But, when I turn right turn signal on, it works normally.

I have changed the relay and both left lamps and the problem continues...

Did any one have some idea how could I fix this?

Thanks for any answer...

[volvodspec]

both left lamps?? do you have a MY76 or MY77 343?

can you post the manufacture/model year of the car, and model type?

[ssiikkssii]

I meant front and rear signal lights...

It is VOLVO 340 1.6 diesel GL.... manufactured 1989...