It is the eighth edition of the event on the shores of Loch Ryan which raises funds for the inshore lifeboat unit.
Toploader follow in the footsteps of Dodgy, S-Club and Ben Haenow in performing at the Dumfries and Galloway festival.
A host of local acts will also take to the stage at Agnew Park this year on Saturday 19 August.

The 20-year-old hit six fours, showing no ill-effects from the break to the same finger that caused him to leave England's winter tour of India early.
Hameed was eventually bowled by seamer Jamie Porter as the visitors reached 319, thanks largely to a counter-attacking 74 from debutant Dale Vilas.
Essex were 35-2 in reply at the close.
After Lancashire opted to bat first, Hameed, playing after being hurt on the same finger practising against the Cambridge students this week, shared a third-wicket stand of 68 with Liam Livingstone.
Steven Croft (48) then gave the visitors' innings impetus, but a flurry of wickets in the afternoon session put Essex in charge as Lancashire were reduced to 160-6.
On his Essex debut, former Lancashire paceman Neil Wagner (3-100) and Aaron Beard (3-47) did the damage, along with the run-out of Shivnarine Chanderpaul on 15 by substitute fielder Callum Taylor.
South African Kolpak signing Vilas struck 10 boundaries as his 101-ball innings to ensure there was no collapse from the visitors, but their total was still looking a little below par when he was the penultimate batsman out with the total on 268.
However, England's James Anderson (13 not out) joined Kyle Jarvis (28) to put on 51 runs in fewer than 10 overs, which frustrated the hosts, taking Lancashire past 300, giving them a third batting point.
Essex faced nine overs before stumps and began their reply solidly enough, but Jarvis and Anderson took a late wicket apiece to give their side a slight edge.
Essex's former Lancashire paceman Neil Wagner told BBC Radio Essex:
"It was tough graft out there. It was a pretty unresponsive wicket. It was quite good batting conditions with no cloud or moisture in the air and not much swing. And they played very well.
"It was a wicket where if you gave yourself time it will work for you and Dane Vilas showed that. Once you got in and set on the wicket you could score freely and for long periods of time.
"It was an outstanding delivery by Jamie Porter to remove Haseeb Hameed. He is a batsman who leaves the ball really well and makes good decisions. So it was a pretty good ball.
"Aaron Beard is an outstanding prospect for Essex. I am very excited watching him bowl. I love working with him, he's a good kid. He's still young and the talent and ability he's got at the moment is something to be very excited about."
Lancashire's England opener Haseeb Hameed told BBC Radio Manchester:
"The finger is fine now. It felt almost back to normal. It was a bit of a freak incident last week, injuring it in the warm-up and it was quite painful when I batted.
"We made the right decision in getting it checked out and thankfully it was all OK. It was the same finger I injured before. I was doing some short-leg practice and trapped it between ball and turf.
"It swelled up quite a lot and became painful. The surgeon has suggested that when there is a bit of time off it might be worth having surgery to take the plate in the finger out.
"I'm looking at the season in very small packages at the moment. It is important for me to just look at the very near future. We've got some important games coming up for Lancs and there is a lot of games to be played for Lancs hopefully before the Test series. I'm very much focused on doing my best for Lancashire."
Toploader have been announced as the headline act at this year's RNLI Parkfest in Stranraer.
[NEXT_CONCEPT]
England opener Haseeb Hameed shook off a hand injury to make a confident 47 as Lancashire edged a see-saw first day of the new season against Essex.