usb audio and mame4all incompatibility ?

[rig]

I recently connected a usb dongle sound card to my rpi3 and it works. However, all of my mame4all roms fail to boot now. They worked fine before I hooked up the dreaded dongle. From what I can gather off the interwebs this is a known issue without a solution. I have 4 questions:

1. does anyone know how to get usb audio working with mame4all?

2. how do I delete script/code/commands I modified with Nano in the command line?

3. Should the 3.5mm jack audio still work now that I have altered the sound priority in Nano? i.e.
   0 snd_usb_audio
   1 snd_bcm2835
   because it is not working for me-with the usb unplugged and the 3.5mm jack plugged in. I am wondering if there is a way to unplug the usb dongle and use the 3.5mm jack when playing mame4all roms.

4. I think I messed up edditing the config file in nano. when I check for sound output priority in the command by typing, "cat /proc/asound/modules" the rpi responds
   "0 snd_usb_audio
   2 snd_bcm2835", the instructions on github state that the rpi should respond,
   "0 snd_usb_audio
   1 snd_bcm2835", it looks to me like I somehow set sound output priority to 2 instead of 1 for the internal sound card. Is this a problem?

here is some background on my setup:

1. rpi 3 overclocked a little bit... I am outputting video via gpio to crt (pvm)
2. retropie 4.2 updated from previous image off this website (you guys rock)
3. I followed the following instructions off, https://github.com/RetroPie/RetroPie-Setup/wiki/Sound-Issues , titled " Alternate USB Audio Method" to install the usb dongle.
4. this b the dreaded dongle, https://www.amazon.com/gp/product/B003UBKR4U
5. all my other roms and cores are working fine with the dreaded dongle. It actually sounds really really good on games with good sound emulation
6. my mame4all roms are the right romset for mame4all

sorry for the length of this post. I tried to make it concise. I have had good experiences on this forum in the past. You guys rock

[rig]

Problem solved. I found an easy solution. I switched emulators. I am using lr-imame4all instead of mame4all. Both emulators use the same romset and perform identically (as far as I can tell). Now all is right with the world.

[BuZz]

@rig if you have a rpi3, you will find lr-mame2003 a better emulator.

[rig]

@BuZz said in usb audio and mame4all incompatibility ?:

@rig if you have a rpi3, you will find lr-mame2003 a better emulator.

Yea, I have lr-mame2003 but I don't use it as much. when I first started using mame I played a few roms on both emulators and came to the conclusion that mame4all worked better. By "worked better" I mean that the sound was cleaner/clearer on a few games and the video resoulution looked sharper on a few games. However I have run into exceptions-- I use lr-mame-2003 for St Dragon because it sounds much better compared to mame4all; I also play x-men on lr-mame 2003 becsuse the sprite shadows look better.
I didn't run a thorough test and I could be mistaken. Maybe I should give lr-mame2003 another go. What do you mean specifically by lr-mame2003 being a better emulator?
I can say that I do prefer lr-mame4all over mame4all because of the retroarch support.

p.s. I am using a rpi3