I’m not sure if it’s a error or not, but while I was searching the area for the Weapon/Collectible, I came across them on a rooftop of a building which I already collected them.
I don’t know if there is another collectible lying around somewhere in the town, but I think that the collectible would be by the weapon on the rooftop.
I’ve been suspecting that’s broken. I picked up the tape yesterday, and it still shows 0/1 for me as well.
I see. I thought it might be glitched on my end, and I’m hoping that it gets fixed. I’m missing about 3 audio tapes which I don’t know where they could be.
There’s definitely something funny going on. I just went back, and the tape wasn’t there (because I’d picked that up), but the pistol was, so I took that to see whether it would count towards the location stats, and it didn’t.
That said, I’m reasonable sure that the roof had tape 3 from row 2, so at least it got counted towards collectibles for me.
Still missing 2 and 4 from row 1, and last tape.
The audio’s that I’m missing would be Row 1 Column 3, Row 2 Column 2, & Row 3 Column 1 if I’m not mistaking, but I’ll double check once I get back online in the game.
I got the weapon from a guy on the beach [3800,109] 3 crown AG 4 and the tape on the roof [accessed using the scaffolding] at 3728, 56 which played for me but didn’t give credit…
It’s a trap…
The collectible can be found somewhere at the festival site… 
Kimosabe is right, the audio tape isn’t glitched, the collectable needed is at the festival events area at 3964, 39, on the main stage, sitting on top of a stage speaker next to the open truck cargo doors