The June 6th edition of the Hypaspace Weekly Podcast features an interview with Jamie. The focus of the discussion is 'Sine Qua Non'. He elaborates further on comments he made in the Zap2It Q&A and, oddly, is asked about a story development involving other characters which he (humorously) tries to answer as best he can. I'd say this interview is spoiler free. His portion of the interview begins at the 16:30 mark and ends at 24:17.
ETA: meshel73 has edited the podcast down to just Jamie's interview segment. It can be downloaded here.