MFC-J690DW 常見問題&故障排除 MFC-J690DW 不是您的產品嗎? 複印品質問題 Solutions for problems related to copy quality 一般複製問題 Solutions for difficulties in copying such as low copy speed, copy noise, and unexpected copy results 複印操作 How-to information about copying 常見問題&故障排除