I've just been looking at the score for Da Slockit. The first note of the B part 14th bar - the bar in which the F# chord is played - is F#. Now - how in all that's holy - how can that be a Bb? Here's the abc - relevant bar in boldface:

X: 1
T: Da Slockit Light
M: 4/4
L: 1/8
R: reel
K: Dmaj
FE|D3F A2d2|fedc d2A2|B2d2 A2d2|BAGF EGFE|D3F A2d2|fedc d2A2|B2G2 AGFE|D4- D2:|g2|f2a2 e3c|d3e dcBA|f2a2 e2^g2|a4- a2=g2|f2a2 e3c|d3e dcBA|B2G2 AGFE|D4- D3g|f2a2 e3c|d3e dcBA|B2d2 A2d2|BAGF EGFE|D3F A2d2|fedc d2A2|B2G2 AGFE|D4- D2|]