Techniques for generating bus interval messages by a downstream USB extension device in a USB extension environment are disclosed. The downstream USB extension device transmits a first outgoing bus interval message in response to receiving a first incoming bus interval message at a first time. An expected time of receipt of a second incoming bus interval message is determined based on the first time. The downstream USB extension device transmits a second outgoing bus interval message at a second time based on a difference between the reception time and the expected time of receipt if the second incoming bus interval message has been received at a reception time before the expected time of receipt. The downstream USB extension device transmits the second outgoing bus interval message at the expected time of receipt if the second incoming bus interval message has not been received before the expected time of receipt.