Silence when answered. Then a computer voice said "Goodbye" and ended the call.So many nuisance calls like this.

I called back number (03) 4383 3954 rang once then goes to busy tone.

Usual delay in speaking, predictable accent. Claimed to be from Telstra. Claimed I had an error and he offered me a discount to fix it. I asked if his parents knew what he did for a living. He hung up. I wish there was a way to catch and jail these bastards. SCAM.