Finding a Shell in a Bose SoundTouch

Bose, every salesperson’s favorite stereo manufacturer, has a line of WiFi connected systems available. It’s an impressively innovative product, able to connect to Internet Radio, Pandora, music libraries stored elsewhere on the network. A really great idea, and since this connects to a bunch of web services, you justĀ know there’s a Linux shell in there somewhere. [Michael] found it.

The SoundTouch is actually rather easy to get into. The only real work to be done is connecting to port 17000, turning remote services on, and then connecting with telnet. The username is root.

The telnet service on port 17000 is actually pretty interesting, and we’re guessing this is what the SoundTouch iOS app uses for all its wizardry. [Michael] put a listing of the ‘help’ command up on pastebin, and it looks like there are commands for toggling GPIOs, futzing around with Pandora, and references to a Bluetooth module.

Interestingly, when [Michael] first suspected there could be Linux inside this box, he contacted Bose support for any information. He figured out how to get in on his own, before Bose emailed him back saying the information is proprietary in nature.

Repairing Bose Active Noise Cancelling Headphones

[Mansour] was disappointed to find out that his Bose QC15 headphones had a dead right channel. These headphones have active noise cancelling, which uses a microphone to capture ambient noise and digital signal processing to insert an out of phase signal. Since they’re quite expensive, [Mansour] was determined to resurrect them.

First, he determined that the right speaker had died, so he found a replacement on eBay. These were designed for a different set of headphones, but matched the impedance of the original Bose part. After replacing the driver, it seemed that the repair was a failure. The sound cancelling wasn’t working, and a the playback was high-pitched. As a last attempt, he potted the speaker with glue, to match the original construction. Much to his surprise, this worked.

The problem was that the new driver didn’t have sufficient sound isolation from the microphone, which is meant to pick up passive noise. This feedback likely caused issues with the noise cancelling DSP. A little glue meant a $20 fix for a $400 pair of headphones.