Before Cardi B and Offset called it quits late last year, it looks like they were dealing with some bozo calling 911 and reporting fake crimes happening at their home ... and some of it was captured on video.

TMZ has obtained police body cam video that was taken in August last year out in Sandy Springs, GA -- where the estranged couple have a home. In an incident report, cops say they were dispatched to their address after calls came in to report someone had been shot there.

One officer notes in the police report that a caller claimed someone fired a shot at a "famous rapper's house" and even suggested Cardi herself may have been hit with a bullet ... so cops came with lights and sirens, and with their firearms drawn.

Fortunately ... cops say the call turned out to be BS -- something officers discovered when they arrived at the property and talked to Offset's uncle, Derrick Cephus, who said he was house-sitting. Yep, it sounds like Cardi and Offset weren't even home for this swatting attempt .... just a confused relative!

Check out the video to see the encounter, 'cause it's pretty wild -- especially when it sounds like Offset gets roped in on the phone, which you can clearly hear from the speaker. It's pretty obvious he was heated about the bogus report ... and perhaps even angrier that officers were there at all.

After some back and forth -- and eventually realizing nothing was wrong -- the cops left and just took a report of the whole thing. Also worth noting ... Offset refers to CB as his "wife" here, and says she's with him in L.A. while all this ruckus is going down back at home.

Now, in terms of how this plays into their current relationship status (complicated), it's hard to say for sure ... but it seems to suggest that whatever happened with their relationship may have been after this.

Meanwhile, this just goes to show ... folks apparently love to screw with stars in the worst way possible.