The star - who recently signed a £400,000 deal with trendy trainer firm Puma - brought some decidedly non-designer boots to brave the mud at the Argyll bash.
But red-faced security guards BANNED the singer from the backstage area...because they didn't recognise him.
The Paisley troubadour had been mingling with fans after wandering off on his own to catch BEARDYMAN's set in the Unknown Pleasures tent.
But when he tried to return to the backstage area, a burly bouncer stretched his arm out and barked: "You're not coming in."
Good on the 21-year-old pop heart-throb, though - he didn't get shirty or pull the old "Do you know who I am?" stunt.
Instead he waited patiently for organisers to figure out he was missing and come to his rescue. When he realised his mistake, the blushing bouncer confided: "It's not every day you get a genuine star trying to blag his way in."
After rejoining his manager in the backstage Speakeasy bar, Paolo said: "I'm having a great time, soaking up the atmosphere.
"Beardyman was wicked - well worth the wee technical hitch with security!"

Friday night's headliners KASABIAN previewed new track Fire - after getting caught up in their own fire alarm drama on the way to the bash.
The Leicester four-piece dropped into Sloans bar in Glasgow city centre for a bite to eat - but just minutes after they arrived the alarm sounded and the pub was EVACUATED.
It didn't seem to dampen their spirits though - when they arrived on site, frontman TOM MEIGHAN was bursting with pride about the band's eagerly-awaited third album.
He beamed: "We're really pleased with it - it's very rootsy, man."
Around 15,000 fans flocked to the three-day festival in the grounds of Inveraray Castle overlooking Loch Fyne.
Yesterday's bill included a cracking set from rising Scots stars GLASVEGAS and one of the day's most energetic performances from St Albans trio FRIENDLY FIRES.
They got the crowd rocking with their rework of the JAMIE PRINCIPLE classic Your Love and crowd fave Jump In The Pool.
Yet MANIC STREET PREACHERS issued the fest's oddest backstage demand.
A festival source said: "They insisted on having Golden Wonder crisps. Everyone else got Walkers but not them."
BLOC PARTY got down and dirty with supermodel AGYNESS DEYN backstage before their headline set on the Oyster Stage. Frontman KELE OKEREKE, 26, revealed: "We've been wallowing about in the mud having a laugh - she's a really cool lass and she's into music too."
FRANZ FERDINAND, electro-folk stars GOLDFRAPP and Icelandic outfit SIGUR ROS will bring the curtain down tonight.
Fans Euan Martin and John Blair, both builders from nearby Dunoon, turned up dressed as superheroes. John, 35, said: "It's the best festival in Scotland."
Additional reporting: KERRY HARVEY, STANA CEPKOVA, DAVID BARR, LORNA SMITH, KEIRON McGUINNESS