Other profiling attempts this morning.
Clean amp profiling.
I had experienced the bug only once, when I have achieved profile refining, don't know if it is the cause.
First attempt: KO
1. XLR Input
2. Single mic
3. No return level adjustment
4. No other input attached
5. Refining
Second and third attempts: OK
1. XLR Input
2. Single mic
3. Return level adjusted
4. No other input attached
5. No refining
I will drop a mail to the support.