diff --git a/src/backups.js b/src/backups.js
index f0f5f3632..dd2a4f151 100644
--- a/src/backups.js
+++ b/src/backups.js
@@ -269,7 +269,7 @@ function sync(backupConfig, backupId, dataDir, callback) {
                 });
             }
         }, iteratorCallback);
-    }, 10 /* concurrency */, function (error) {
+    }, backupConfig.syncConcurrency || 10 /* concurrency */, function (error) {
         if (error) return callback(new BackupsError(BackupsError.EXTERNAL_ERROR, error.message));
 
         callback();
diff --git a/src/routes/settings.js b/src/routes/settings.js
index 850577e3c..264d42934 100644
--- a/src/routes/settings.js
+++ b/src/routes/settings.js
@@ -153,6 +153,10 @@ function setBackupConfig(req, res, next) {
     if (typeof req.body.provider !== 'string') return next(new HttpError(400, 'provider is required'));
     if (typeof req.body.retentionSecs !== 'number') return next(new HttpError(400, 'retentionSecs is required'));
     if ('key' in req.body && typeof req.body.key !== 'string') return next(new HttpError(400, 'key must be a string'));
+    if ('syncConcurrency' in req.body) {
+        if (typeof req.body.syncConcurrency !== 'number') return next(new HttpError(400, 'syncConcurrency must be a positive integer'));
+        if (req.body.syncConcurrency < 1) return next(new HttpError(400, 'syncConcurrency must be a positive integer'));
+    }
     if (typeof req.body.format !== 'string') return next(new HttpError(400, 'format must be a string'));
     if ('acceptSelfSignedCerts' in req.body && typeof req.body.acceptSelfSignedCerts !== 'boolean') return next(new HttpError(400, 'format must be a boolean'));
 
diff --git a/src/storage/s3.js b/src/storage/s3.js
index bfbc35194..bfb7a4a51 100644
--- a/src/storage/s3.js
+++ b/src/storage/s3.js
@@ -75,7 +75,8 @@ function getCaasConfig(apiConfig, callback) {
                 customBackoff: () => 20000 // constant backoff - https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/Config.html#retryDelayOptions-property
             },
             httpOptions: {
-                connectTimeout: 10000 // https://github.com/aws/aws-sdk-js/pull/1446
+                connectTimeout: 10000, // https://github.com/aws/aws-sdk-js/pull/1446
+                timeout: 300 * 1000 // https://github.com/aws/aws-sdk-js/issues/1704 (allow 5MB chunk upload to take upto 5 minutes)
             }
         };
 
@@ -107,7 +108,8 @@ function getS3Config(apiConfig, callback) {
             customBackoff: () => 20000 // constant backoff - https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/Config.html#retryDelayOptions-property
         },
         httpOptions: {
-            connectTimeout: 10000 // https://github.com/aws/aws-sdk-js/pull/1446
+            connectTimeout: 10000, // https://github.com/aws/aws-sdk-js/pull/1446
+            timeout: 300 * 1000 // https://github.com/aws/aws-sdk-js/issues/1704 (allow 5MB chunk upload to take upto 5 minutes)
         }
     };