There is always a pop when sound format changes as well. For example, if watching Blu-rays where trailers, menus, and warning screens all tend to have various sound formats, and change each time. This will cause the X7 to pop. I.e. A trailer can be encoded in Dolby, then the next screen is PCM, then back to Dolby, etc. Each time the X7 has to decode a different format, the pop occurs. Limit this by just lowering the volume near zero until the movie starts.