diff --git a/services/track-changes/app.coffee b/services/track-changes/app.coffee
index 43cddca498..a83d78c7f1 100644
--- a/services/track-changes/app.coffee
+++ b/services/track-changes/app.coffee
@@ -61,7 +61,7 @@ app.post "/pack", (req, res, next) ->
 	else
 		logger.log "running pack"
 		packWorker = child_process.fork(__dirname + '/app/js/PackWorker.js',
-			[req.query.limit, req.query.delay, req.query.timeout])
+			[req.query.limit || 1000, req.query.delay || 1000, req.query.timeout || 30*60*1000])
 		packWorker.on 'exit', (code, signal) ->
 			logger.log {code, signal}, "history auto pack exited"
 			packWorker = null
diff --git a/services/track-changes/app/coffee/PackWorker.coffee b/services/track-changes/app/coffee/PackWorker.coffee
index 563973d13a..12c4a37aff 100644
--- a/services/track-changes/app/coffee/PackWorker.coffee
+++ b/services/track-changes/app/coffee/PackWorker.coffee
@@ -22,7 +22,7 @@ source = process.argv[2]
 DOCUMENT_PACK_DELAY = Number(process.argv[3]) || 1000
 TIMEOUT = Number(process.argv[4]) || 30*60*1000
 
-if source.match(/[^0-9]/)
+if !source.match(/^[0-9]+$/)
 	file = fs.readFileSync source
 	result = for line in file.toString().split('\n')
 		[project_id, doc_id] = line.split(' ')