[fluid-dev] Connect fluidsynth to particular device

[Crypto]

Hi to all here at fluid-dev,

fluidsynth has options to make it use a particular audio driver (such as alsa, 
jack, oss), but how can I make fluidsynth connect to a particular sound card?

Let's say I use fluidsynth with the alsa driver, and now I have two devices 
that could be used (like an internal onboard sound or an external hotplugging 
USB device). How can I connect fluidsynth to USB sound device explicitely?

I know that I should use jack and qjackctl for it all and it works, but 
sometimes I would like to do it without jack.

I am stuck here because I have an external MIDI device (Edirol UM-2) and 
fluidsynth wants to connect its audio driver part to it. It regards the MIDI 
device as "default" audio device.

The error I am getting when running fluidsynth and the alsa driver part:

"ALSA lib pcm_dmix.c:1008:(snd_pcm_dmix_open) unable to open slave
fluidsynth: error: Failed to open the "default" audio device
Failed to create the audio driver"

and aplay -L tells me that the MIDI device is considered to be the default 
audio device, which is nonsens really. In the list it shows up as first 
default device to fluidsynth wants to connect to that.

aplay -L

"default:CARD=UM2
    Default Audio Device
null
    Discard all samples (playback) or generate zero samples (capture)
default:CARD=NVidia
    HDA NVidia, ALC260 Analog
    Default Audio Device"

Do I really have to dig into 
this 
.asound.conf-multiple-cards-hotplug-USB-automagically-script-switching-thing 
that has never worked for me or is there an easier way of doing it and I am 
missing something?

Thanks for any hint here and kind regards,
Crypto.