The GSA 70 uses the same hardware as the BTD 800, but with a different grey colored housing.
The GSA 70 also uses the same basic firmware functions with the BTD 800. The GSA 70 is focused on the gaming-related use cases, and some firmware functionality has been removed - mainly related to advanced call control functions.
The GSA 70 supports dual end-point by enumerating as two separate audio-devices - one for communication and one for main audio. The communication end-point is used for chat, Skype, Discord etc where main audio is used for music, game and system sound.
The main audio channel is optimized for low latency of the audio signal, by optimized package size and reduced buffer size.