It may be a possibility, many years ago I had a Getaway on sight in a pub. I would get a call to say the supercharger was not functioning, the balls would go into the loop and then just roll back without being accelerated through. When I got there the game was fine. This happened about 3 times so I asked if it was the3 same person complaining. Turns out it was some guys coming in at about 5pm for after work drinks and a game of pinnie. I went in and joined them and sure as nuts the supercharger failed a couple of times (not every time) while they were playing. I noticed at this time the sun was getting low in the sky and shining at a narrow angle through a window onto the top end of the play field and into the supercharger magnet/coil housing (there are 3 optos in there too). Turns out for that hour or so (probably also dependent on time of year) that the sun light was disrupting the opto switches, or at least the first one). Moved the game about a metre to the right and never had that problem again. As other's have said try a cowling with the LEDs and see if that helps.
Interesting problem, lucky you asked the right questions and checked it out, would have been a pain to chase without seeing it first hand
