Labatts Blue is about a 2.5 vol. beer. At 37 F beer temperature, should require 13 PSIG. Have you conducted a pressure leak test? Leaks can cause dispensing issues. At 9 PSIG eventually the beer will pour fine once you have degassed it enough. At this time the beer will be flat.
Scott Zuhse, Instructor
Micro Matic Dispense Institute