error in: sudo grunt

[SelaOr]

Initializing
Command-line options: --verbose, --gruntfile=/home/ors/dev/external/smart_tv/popcorntime-smarttv/Gruntfile.js

Reading "Gruntfile.js" Gruntfile...OK

Registering Gruntfile tasks.
Reading package.json...OK
Parsing package.json...OK
Initializing config...OK

Registering "grunt-sync" local Npm module tasks.
Reading /home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/grunt-sync/package.json...OK
Parsing /home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/grunt-sync/package.json...OK
Loading "sync.js" tasks...ERROR

TypeError: Cannot read property 'length' of undefined
at exports.convertNodeAsyncFunction (/home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/promised-io/promise.js:633:28)
at Object. (/home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/promised-io/fs.js:27:16)
at Module._compile (internal/modules/cjs/loader.js:688:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:699:10)
at Module.load (internal/modules/cjs/loader.js:598:32)
at tryModuleLoad (internal/modules/cjs/loader.js:537:12)
at Function.Module._load (internal/modules/cjs/loader.js:529:3)
at Module.require (internal/modules/cjs/loader.js:636:17)
at require (internal/modules/cjs/helpers.js:20:18)
at Object. (/home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/grunt-sync/tasks/sync.js:1:72)

Registering "grunt-contrib-watch" local Npm module tasks.
Reading /home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/grunt-contrib-watch/package.json...OK
Parsing /home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/grunt-contrib-watch/package.json...OK
Loading "watch.js" tasks...OK

• watch

Registering "grunt-samsungstv-packager" local Npm module tasks.
Reading /home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/grunt-samsungstv-packager/package.json...OK
Parsing /home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/grunt-samsungstv-packager/package.json...OK
Loading "samsung.js" tasks...OK

• samsung

Registering "grunt-contrib-jshint" local Npm module tasks.
Reading /home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/grunt-contrib-jshint/package.json...OK
Parsing /home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/grunt-contrib-jshint/package.json...OK
Loading "jshint.js" tasks...OK

• jshint

Registering "grunt-contrib-requirejs" local Npm module tasks.
Reading /home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/grunt-contrib-requirejs/package.json...OK
Parsing /home/ors/dev/external/smart_tv/popcorntime-smarttv/node_modules/grunt-contrib-requirejs/package.json...OK
Loading "requirejs.js" tasks...OK

• requirejs
  Loading "Gruntfile.js" tasks...OK
• build, default, deploy

No tasks specified, running default tasks.
Running tasks: default

Running "default" task

Running "build" task
Warning: Task "sync:assets" not found. Use --force to continue.

Aborted due to warnings.