High quality and timely assessment feedback is central to student learning in higher education; however, written feedback has many limitations. One of the innovative approaches to delivering feedback to EFL learners is individualized audio-visual feedback (AVF) using screencast technology. Previous research on AVF has been extensively descriptive and mostly focused on student preferences for feedback and evaluation of various screencast software. The present study employed a mixed-method design using pre-post writing tasks and pre-post questionnaires to investigate what particularly beneficial affordances this type of media-rich feedback might offer for writers in the English-Medium Instruction (EMI) classroom, to identify the effects of AVF on changes in learners' motivation, and to explore students' perceptions towards screencast feedback. The results suggest that AVF is positively received by EFL learners and that simultaneous visual cues and detailed explanations promote better understanding, engagement, and active listening. In addition, AVF significantly improves learners' writing performance and academic motivation. The paper concludes with practical implications and suggestions for further research.