Every 3-run pass I’m doing from LA for Chrome appears to be failing at least one pass. For instance, the most recent run failed passes 1 and 3 with ‘Test Error: Failed to configure IPFW/dummynet. Is it installed?’ whereas the 2nd pass completed OK.
Example test (Chrome): http://www.webpagetest.org/result/140630_DS_C88/
Example test (Firefox): http://www.webpagetest.org/result/140630_AZ_C8Z/