Symptom: Kemper Profiler Amp (KPA) did not recognize USB
Brand new KPA did not recognize multiple USB sticks. I could not update or import any rigs. When I plugged any USB stick to format it with the KPA, no USB menu appeared and the KPA froze up. If I turned the know, it would not change to Tuner mode or any other mode. It would not even shut down properly (did not show the "Shutting down" screen; it simply displayed whatever was there and shut off after about half a minute). My KPA came with an OS 7.1... version. I formatted several USB sticks and still the KPA did not recognize them.
Solution:
1 - Found an old USB stick (an old promotional 4 Gigabyte USB stick with no brand name on it). An old thread says some brands (like PNY) have not worked with the KPA.
2 - On PC, found USB on Explorer (Windows 10).
3 - Right click on the USB drive in Explorer and clicked on "Format".
4 - In the Format USB Drive window, I set:
- File system: "FAT32 (Default)"
- Allocation unit size: "32 kilobytes"
- Format options: I unchecked "Quick Format"
- then I clicked 'Start'
The process took several minutes. (NB: Formatting a USB drive erases all its contents.)
5 - After formatting the USB drive, I plugged into the KPA. I had just turned on the KPA and had the main knob in the Tuner setting.
6 - I turned the knob to the Browser setting and voila it showed a USB menu under the third white button from the left to the right (just on top of the screen). From that menu I formatted the USB in the KPA and was later able to proceed with updates. (I needed to update to OS 7.3.2 then update again to the latest version 8.0... I had to search for old updates in the Kemper webpage.)
NB: After formatting the USB with the KPA, I placed the update (kaos.bin) file in the root menu. I DID NOT copy the file in one of the folders created by the KPA.
I do not think that plugging the USB in Tuner mode prior to choosing Browser mode was necessary for the KPA to recognize it. But, that maneuver had been mentioned in an old thread and I was too superstitious to improvise after myriad attempts. If someone has this same problem and plugs the USB directly in the Browser mode and it works...please, place a comment so as to solve this mystery.
I hope this information serves someone well one day. Do not give up, the KPA is a beyond amazing experience.