Newbee - Use Moode on "pur" RPi 3B+

[UpsiUps]

Hi,

I just tried Moode with a HifiBerry Digi+pro and it worked great and easy from the beginning. Saying that, I had it connected with three wires: power, S/PDIF and Ethernet. Now I want to reduce the wires and the HW. I am stuck , when I try to play music over BT without the HifiBerry HAT. I configured the I2S Audiodevice to "None", I can connect the Speakers through BT, but when I try to play a title, I get the following message:

Code:

MPD error

Failed to open "ALSA bluetooth" [alsa]; Error opening ALSA device "btstream"; snd_pcm_hw_params() failed: Invalid argument

My /boot/config.txt looks like the following:

Code:

disable_splash=1
#hdmi_drive=2
dtparam=i2c_arm=on
#dtparam=i2s=on
#dtparam=audio=on
#dtoverlay=pi3-disable-wifi
#dtoverlay=pi3-disable-bt

So I currently disabled i2s, hdmi ( headless ) and dtparam(audio). Enabling all or partial don't make the difference. 
with systemctl list-units I get

Code:

sys-subsystem-bluetooth-devices-hci0.device                                                          loaded active plugged   /sys/subsystem/bluetooth/devices/hci0                                                
● bluealsa-aplay@CC:90:93:0B:C2:97.service                                                             loaded failed failed    BlueAlsa-Aplay                                                                        
 bluealsa.service                                                                                     loaded active running   BluezAlsa proxy                                                                      
 bluetooth.service                                                                                    loaded active running   Bluetooth service                                                                    
 system-bluealsa\x2daplay.slice                                                                       loaded active active    system-bluealsa\x2daplay.slice                                                        
 bluetooth.target                                                                                     loaded active active    Bluetooth                     

which shows that bluealsa-aplay is not running. And now I am stuck   Any suggestions ?