We have recently noticed a problem with the data being returned for a request with the following filters:
ga:source==google;ga:medium==organic,ga:medium==cpc
This should report data for traffic with the source of "google" and a medium of either "organic" or "cpc" and has worked without problem in the past. This is now returning all zeroes for some domains (it seems to be limited to domains that have cpc traffic).
Interestingly, the following filters for the same domain return non-zero data:
ga:source==google;ga:medium==organic
ga:source==google;ga:medium==cpc
ga:source==bing;ga:medium==organic,ga:medium==cpc
Here is a full example request (with the profile id removed) that is failing:
https://www.googleapis.com/analytics/v2.4/data?ids=ga: 000000&dimensions=ga:date&metrics=ga:pageviews,ga:visits,ga:timeOnSite,ga:bounces&sort=ga:date&filters=ga:source%3D%3Dgoogle;ga:medium%3D%3Dorganic,ga:medium%3D%3Dcpc&start-date=2013-04-20&end-date=2013-05-19&start-index=1&max-results=1000