Welcome to the Bose Community! We appreciate you posting and are sorry to see that your first Community post is due to a power issue with your SoundTouch 520.
Can you please let us know if you see any LED's on the system at all? These LED's can be seen on the back on the Acoustimass Module or on the Wireless Link Adapter.
If you are unable to see any LED's on either system, this would indicate to me that there is an issue with the SoundTouch 520 and that it would need to be repaired. To proceed with this please reach out to us via any of the contact methods listed here, so the team can assist further.
If you are able to see LED's please follow these troubleshooting steps here to resolve your issue.
Please do let us know if you have any further questions.
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