Firmware Version 1.0.6 (May 2025)
Download Link:
Release Notes:
Fix/solution for the following issue:
"System becomes unresponsive while the display shows an update message"
The ULTIMA 25 AKTIV does not respond to any inputs, is "frozen," and the display shows: "Update, please connect to PC." The device can no longer be operated, and nothing happens when connecting to a PC.
Solution: Manually apply the update
Firmware Version 1.0.12 (June 2026)
Download Link:
https://docs.teufel.de/download/firmware/ultima_25_aktiv/ultima25A_app_v1_0_12.zip
Release Notes:
- Fixed an issue where an undesirable volume reduction occurred in the calibration menu
- Volume calibration setting for front/rears/subwoofer can now be saved during power interruption/ and wireless reset
- Calibration levels for front, rear, and subwoofer channels now apply reliably after a power cycle.
- Added a Bluetooth on/off option in the display menu so you can disable Bluetooth without removing paired devices
- Reduced audible clicks or pops when switching between sources or power cycle
- More accurate per-channel levels during the calibration process
- Improved reset (unpair) flow for rear speakers and subwoofer, including correct restoration of sound settings afterward
- Optical auto-on now defaults to off for predictable behavior out of the box
Manually Applying the Update
Step-by-step instructions:
- First, download the zip file.
- Extract the file and note the location. Note for Mac users: You may need a separate program to extract the file.
- Prepare the speaker for the software update via the menu.
► Note: If the display shows "Update, please connect to PC," the speaker is already waiting for an update and does not need to be prepared again. In this case, proceed to step 5. - Select "Update" in the menu. Menu path: System ► Software ► Update
- The display will show "Start?". Press the SELECT button to start the update. The display will show "Update." The POWER button will blink red.
- Connect the ULTIMA 25 AKTIV to a PC using a USB-C data cable.
- On the Windows PC, a USB drive named “ULTIMA 25 AKTIV” or "Teufel" will appear. Move or copy the previously extracted file to this drive. This process may take a few seconds.
- The update will be automatically detected and applied. The update runs in several sections, and multiple messages about the progress will appear on the display.
- Once the display prompts you to press the "Select button to restart," you can complete the update by pressing the button on the remote control.
- The system will restart and will then be ready for use.
How do I check the firmware version of the ULTIMA 25 AKTIV?
You can check the software version through the menu of the ULTIMA 25 AKTIV.
Follow these steps:
Menu path: System → Software → Version.
The software version will then be displayed.