asked to call re investigation ?

Long story short: CRA hoax call. Don't answer or call back.

I got a voicemail from this number. The voicemail was cut off from the beginning which leads me to believe it's an automated message:
"...that there is a federal investigation on your name, as your account was found suspicious in the audit report. You need to call me back on my number, that is 613-366-7039. I repeat -- 613-366-7039. Don't try to disregard the message, or else it will be taken as an offense on your end. Again, this is Officer Jonathan Knight from Revenue Canada."

Google search on the message led me to this site with a similar message :
https://esterhazyonline.wordpress.com/2015/07 ... -hoax-cra-call/

I also got this call exactly as you are describing today.  Before calling back, I checked on google and found this message!

I got this call 3 times today i didnt answer but left that same message all 3 times , its a hoax dont give out any personal info , i even called the rcmp to tell them about and they told me to not answer or call back

I received a call which left a message from this number today twice.  Same message.  Didn't return call as I figured it might be a hoax which I now see I was correct in thinking this.