So, tried again.
The param in /etc/default/macchanger is set to "=true"
# before bringing up any network interface, run macchanger. Careful, this is
# not guaranteed to prevent leaking your real MAC address before the new one
# gets assigned!
#
ENABLE_ON_POST_UP_DOWN=true
# by default, macchanger runs on all network interfaces but loopback (lo). If
# you only want it to run on specific network interfaces, set them here:
#
#ENABLE_INTERFACES="wlan0"
Hoqwever, it looks, somewhere the IFACE variable is wrong set. But it looks like, this is not set by macchanger.
I searched through all configs below /etc, but could not find any.
This is the log output of macchanger:
IFACE = --all
/usr/bin/macchanger: unrecognized option '--all'
GNU MAC Changer
Usage: macchanger [options] device
-h, --help Print this help
-V, --version Print version and exit
-s, --show Print the MAC address and exit
-e, --ending Don't change the vendor bytes
-a, --another Set random vendor MAC of the same kind
-A Set random vendor MAC of any kind
-p, --permanent Reset to original, permanent hardware MAC
-r, --random Set fully random MAC
-l, --list[=keyword] Print known vendors
-b, --bia Pretend to be a burned-in-address
-m, --mac=XX:XX:XX:XX:XX:XX
--mac XX:XX:XX:XX:XX:XX Set the MAC XX:XX:XX:XX:XX:XX
Report bugs to https://github.com/alobbs/macchanger/issues
IFACE = lo
ignoring loopback
Hope this helps.
Best
Hans