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Nebula X1 Pro has an integrated HDMI eARC channel inside the unit and is directly connected to the Dolby Atmos chip to support wireless 7.1.4 multi-channel audio output. 

Currently, the device does not support external sound system, if you need to cover a larger area, you can use 7.1.4 Loudness mode and reasonable placement to maximize the sound pressure effect.Therefore, there is no additional independent HDMI eARC port reserved on the outside, and instead, the device provides a unified HDMI 1 port to satisfy the access of conventional signal sources (such as game consoles, Blu-ray players, set-top boxes, computers, etc.).

The advantage of this design is that users can enjoy the full 7.1.4 channel immersive sound experience without the need for an additional HDMI eARC connector.

In other words, we didn't reduce the eARC functionality, but rather realized wireless multichannel through the internal channels, while retaining the regular use of the external HDMI port.

By hardware design, the X1 Pro supports connecting external speakers via Bluetooth. However, due to the Bluetooth transmission scheme, third-party speakers can only output stereo sound (2.0) when paired with the X1 Pro, and are unable to realize the effect of multi-channel reproduction.

In contrast, the X1 Pro's built-in 7.1.4 panoramic sound system delivers a more stereo, immersive, theater-quality soundstage experience. Therefore, we recommend that users use the X1 Pro's own AV system directly for optimal viewing and listening.

If you have any other questions, please don't hesitate to contact Nebula Customer Support at service@soundcore.com  for further assistance.