To be able to reliably use ALSA audio you need to set a card name, not just "Default"

In a terminal window enter:
cat /proc/asound/card*/id

You should get something like:

PCH
K6

Go into Yoshimi->Settings->Alsa and in Alsa Audio Device enter (say) hw:PCH

This ensures you will always connect to this card at startup regardless of the order this and other ones.

Another benefit of doing this is that ALSA will now use Yoshimi's internal buffer size, otherwise it will force Yoshimi to accept its default size.

You can also set the sample rate - bear in mind that not all cards can use all of these but 44100 and 48000 are almost always available.

If you set a Midi Device as well (such as a keyboard) Yoshimi will try to find and connect to this at startup.

To find your midi devices try:
grep Client /proc/asound/seq/clients
