ProjectCacheWorker failing with Rugged::ReferenceError: Reference 'refs/heads/master' not found

Recently upgraded to GitLab 8.7.4 and I am now getting a few projects that are generating the following error from sidekiq:

2016-05-17_10:16:43.69569 2016-05-17T10:16:43.695Z 31678 TID-1192vg WARN: {"class"=>"ProjectCacheWorker", "args"=>[17432], "retry"=>true, "queue"=>"default", "jid"=>"053b617dcf7ff4e9fca8bf62", "created_at"=>1463478862.7504828, "enqueued_at"=>1463480203.657377, "error_message"=>"Reference 'refs/heads/master' not found", "error_class"=>"Rugged::ReferenceError", "failed_at"=>1463478864.0786626, "retry_count"=>6, "retried_at"=>1463480203.6946769}

The projects exist and the repository has content but there is no master branch, the default branch is showing correctly in the project settings.