Sporadically, controller does not boot (corrected from V3.9.1)

Corrected from: 
c300 controller V3.9.1
p300 controller V3.9.1

Response of the new version:
The c300 and p300 controllers boot correctly.
 
What happens?
The c300 and p300 controllers do not boot.
 
When does this behaviour occur?
With version V3.9.0, the c300 /p300 may sporadically get stuck when booting.
 
Which products are affected?
c300 controller V3.9.0
p500 controller V3.9.0
 
Short-term measures:
Switch the mains for the controller.
 
Evaluation/recommendations:
Sporadically, the c300 and p300 controllers do not boot. Please contact the Lenze Service.

URL for linking this AKB article: https://www.lenze.com/en-de/go/akb/201500402/1/
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