When I go to open packs, usually 3 or more, which is when the set's thematic music comes on, the music plays for a few moments, but then suddenly stops, and then the background ambience also suddenly stops. Sound effects still work, but ambience and music both stop permanently until the client is relaunched. This has happened with Bloomburrow packs and Duskmourn packs, I haven't tested any others. The only way to fix it that I've found is to relaunch the client.