After swapping AudioHat no sound

[hopwon]

Hi
I am unable to get my new IQAudioHQ AMP+ card to output any sound on my existing system. I used to have the Innomaker Audio hat which I had configured and was working fine.
Now with the IQ audio I cannot get any sound output. It should be a simple matter of changing the drive in /boot/config.txt, which I have done but still no sound.
To test the card I created a stock image of RP OS and followed the instructions to install the card and this works so we know the card is ok.
However providing the same edits in my existing system no sound.
I have tested and checked the ALSA config as much as my capabilities allow and everything looks OK.
Perhaps a symptom is that if, in the RP menu I change the volume to a reasonable value, if the playback device is PCM the volume resets to zero

dmesg: https://pastebin.com/HcxntMmK
aplay -L: pi@pacman:~ $ aplay -L
null
Discard all samples (playback) or generate zero samples (capture)
jack
JACK Audio Connection Kit
pulse
PulseAudio Sound Server
default
Playback/recording through the PulseAudio sound server
sysdefault:CARD=IQaudIODAC
IQaudIODAC, IQaudIO DAC HiFi pcm512x-hifi-0
Default Audio Device
dmix:CARD=IQaudIODAC,DEV=0
IQaudIODAC, IQaudIO DAC HiFi pcm512x-hifi-0
Direct sample mixing device
dsnoop:CARD=IQaudIODAC,DEV=0
IQaudIODAC, IQaudIO DAC HiFi pcm512x-hifi-0
Direct sample snooping device
hw:CARD=IQaudIODAC,DEV=0
IQaudIODAC, IQaudIO DAC HiFi pcm512x-hifi-0
Direct hardware device without any conversions
plughw:CARD=IQaudIODAC,DEV=0
IQaudIODAC, IQaudIO DAC HiFi pcm512x-hifi-0
Hardware device with all software conversions
usbstream:CARD=IQaudIODAC
IQaudIODAC
USB Stream Output

pi@pacman:~ $ cat /etc/asound.conf
pcm.!default {
type hw
card 0
}

ctl.!default {
type hw
card 0
}

alsa.conf: https://pastebin.com/HPaXdXCj

aplay output: https://pastebin.com/1Hib9686

/boot/config.txt https://pastebin.com/KNYn9cxU

I've spent hours trying to research and fix this but I am out of ideas so would appreciate some help from an expert :)

Bottom line is swapping the innomaker HAT for the IQAudio HAT = no sound.
Put the IQAudio HAT on a default PI build and it works fine.
If I put the Innomaker HAT back on my original PI and change the driver back it works fine.

Is there a way to uninstall the complete sound system and reinstall as this would be my next step.

Thanks and regards

[hopwon]

@hopwon Update:
Removed pulse-audio with apt-get, and then I get an error message during speaker-test:

pi@pacman:~ $ speaker-test -t2 -c2 -twav -Dhw

speaker-test 1.1.8

Playback device is hw
Stream parameters are 48000Hz, S16_LE, 2 channels
WAV file(s)
Playback open error: -16,Device or resource busy

So I shutdown (exited) RP gui and lo and behold speaker test now works!:

pi@pacman:~ $ speaker-test -t2 -c2 -twav -Dsysdefault

speaker-test 1.1.8

Playback device is hw
Stream parameters are 48000Hz, S16_LE, 2 channels
WAV file(s)
Rate set to 48000Hz (requested 48000Hz)
Buffer size range from 128 to 131072
Period size range from 64 to 65536
Using max buffer size 131072
Periods = 4
was set period_size = 32768
was set buffer_size = 131072
 0 - Front Left
 1 - Front Right
Time per period = 0.715188
 0 - Front Left
 1 - Front Right
...
...

So I started RP back up again and no sound but I get the "startup sound" from the IMP music player I have for the menu which got me thinking somehow the IMP program is blocking the sound card. So I "stopped" IMP and now its working as designed. I think I will uninstall/reinstall IMP with the new Sound Card

[hopwon]

That did the trick, uninstall IMP using the install script to do the uninstall.
Check all the sound was working as expected and it was
Reinstall of imp and I have audio goodness coming out of my Arcade Machine again :)