Called but left no message. Probably scam

Caller: I don't know

This number also called me - as per my usual policy, if the number is not known to me I usually don't answer; if they genuinely need to talk to me they can leave a message. But as is usual with "serial pests" (Telemarketers, Surveys, Scams, etc), this one did not leave a message; ... hence I will not take the call or call back.

Garbled message left on voicemail - indecipherable. Received two calls.
Called the number back - rang for a while then disconnected without anyone answering. Second time I rang back got the old "Your call could not be connected" message from Telstra. Most probably marketing. Blocked the number

I called back number 0405 110 934 spoke to a woman but did not say for what company.