Too much booze?
Possible. . . but one snifter of excellent Brandy is usually not enough to qualify. I'd allow some mixture of the Brandy with spa chemicals but we don't use many that way. . . minimal only after we get out. . . and by the next day, the test strip shows none left. Besides see the photos I've been able to bring out. Booze doesn't show the DTs and pink elephants on photos.