immediate disassociated with hostapd 2.9. 2.5 work fine

[tom]

Hello,

i'm trying to upgrade to 2.9 and am now no longer able to connect to
the WPA-PSK AP.

config (/etc/hostapd-psk-emmy.conf) :

logger_syslog=-1
logger_syslog_level=0
logger_stdout=-1
logger_stdout_level=0
interface=uap0
ctrl_interface=/var/run/hostapd
driver=nl80211
ssid=myssid
hw_mode=g
channel=6
macaddr_acl=0
auth_algs=1
ignore_broadcast_ssid=0
wpa=2
wpa_passphrase=1234567890
wpa_key_mgmt=WPA-PSK

hostapd 2.9 output:

#./hostapd -e /root/entropy /etc/hostapd-psk-emmy.conf
Configuration file: /etc/hostapd-psk-emmy.conf
rfkill: Cannot open RFKILL control device
Using interface uap0 with hwaddr d4:ca:6e:6a:6a:59 and ssid "myssid"
uap0: interface state UNINITIALIZED->ENABLED
uap0: AP-ENABLED
uap0: STA 8c:83:e1:25:a8:d0 IEEE 802.11: authentication OK (open system)
uap0: STA 8c:83:e1:25:a8:d0 MLME:
MLME-AUTHENTICATE.indication(8c:83:e1:25:a8:d0, OPEN_SYSTEM)
uap0: STA 8c:83:e1:25:a8:d0 MLME: MLME-DELETEKEYS.request(8c:83:e1:25:a8:d0)
uap0: STA 8c:83:e1:25:a8:d0 IEEE 802.11: authenticated
uap0: STA 8c:83:e1:25:a8:d0 IEEE 802.11: disassociated

hostapd 2.5 has no problem:

hostapd -e /root/entropy /etc/hostapd-psk-emmy.conf
Configuration file: /etc/hostapd-psk-emmy.conf
rfkill: Cannot open RFKILL control device
Using interface uap0 with hwaddr d4:ca:6e:6a:6a:59 and ssid "myssid"
uap0: interface state UNINITIALIZED->ENABLED
uap0: AP-ENABLED
uap0: STA 8c:83:e1:25:a8:d0 IEEE 802.11: associated
uap0: STA 8c:83:e1:25:a8:d0 WPA: event 1 notification
uap0: STA 8c:83:e1:25:a8:d0 WPA: start authentication
uap0: STA 8c:83:e1:25:a8:d0 IEEE 802.1X: unauthorizing port
uap0: STA 8c:83:e1:25:a8:d0 WPA: sending 1/4 msg of 4-Way Handshake
uap0: STA 8c:83:e1:25:a8:d0 WPA: received EAPOL-Key frame (2/4 Pairwise)
uap0: STA 8c:83:e1:25:a8:d0 WPA: sending 3/4 msg of 4-Way Handshake
uap0: STA 8c:83:e1:25:a8:d0 WPA: received EAPOL-Key frame (4/4 Pairwise)
uap0: AP-STA-CONNECTED 8c:83:e1:25:a8:d0
uap0: STA 8c:83:e1:25:a8:d0 IEEE 802.1X: authorizing port
uap0: STA 8c:83:e1:25:a8:d0 RADIUS: starting accounting session
BA96378E-00000000
uap0: STA 8c:83:e1:25:a8:d0 WPA: pairwise key handshake completed (RSN)

how can i find out why hostapd 2.9 immediately disassociates ?
i've already set the logging to the highest level

any pointers on how to continue from here would be great.
has anything changed between 2.5 and 2.9 so the driver i'm using ?
(latest version of rtl8192eu)