hdac0: Unexpected unsolicited response from address 0: 00000000

Hello list,

on a Lenovo E540 I get this weird error since I used 12-STABLE/CURRENT
on this specific notebook. I guess it has a Optimus Intel iGPU/nVidia
NV940 GPU system and usable is only the iGPU with port
graphics/drm-fbsd12.0-kmod.

The notebook doesn't have audio anymore, nor can I use vlc, mplayer or
smplayer anymore, the applications are stuck as they are waiting for
the audio which never comes up. The same in Firefox (recent versions),
videos, i.e. via youtube, never played since a while now.

I can't say when this problem first occured, it is now for a while, say
6 or 8 months so. I receive massive kernel messages on the console like

[...]
hdac0: Unexpected unsolicited response from address 0: 00000000
hdac0: Unexpected unsolicited response from address 0: 00000000
hdac0: Unexpected unsolicited response from address 0: 00000000
[...]

What is wrong here?

Thanks,

oh

The dmesg shows:

---<<BOOT>>---
Copyright (c) 1992-2019 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
        The Regents of the University of California. All rights
reserved.
FreeBSD is a registered trademark of The FreeBSD Foundation.
FreeBSD 12.0-STABLE #61 r351164: Sat Aug 17 08:37:38 CEST 2019
    root_at_toedd:/usr/obj/usr/src/amd64.amd64/sys/TOEDD amd64
FreeBSD clang version 8.0.1 (tags/RELEASE_801/final 366581) (based on
LLVM 8.0.1)
VT(efifb): resolution 1920x1080
module zfsctrl already present!
module_register: cannot register tmpfs from kernel; already loaded from
tmpfs.ko
Module tmpfs failed to register: 17
CPU: Intel(R) Core(TM) i5-4200M CPU _at_ 2.50GHz (2494.28-MHz K8-class CPU)
  Origin="GenuineIntel"  Id=0x306c3  Family=0x6  Model=0x3c  Stepping=3
  Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
  Features2=0x7fdafbbf<SSE3,PCLMULQDQ,DTES64,MON,DS_CPL,VMX,EST,TM2,SSSE3,SDBG,FMA,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,MOVBE,POPCNT,TSCDLT,AESNI,XSAVE,OSXSAVE,AVX,F16C,RDRAND>
  AMD Features=0x2c100800<SYSCALL,NX,Page1GB,RDTSCP,LM>
  AMD Features2=0x21<LAHF,ABM>
  Structured Extended
Features=0x27ab<FSGSBASE,TSCADJ,BMI1,AVX2,SMEP,BMI2,ERMS,INVPCID,NFPUSG>
  Structured Extended Features3=0x9c000000<IBPB,STIBP,L1DFL,SSBD>
  XSAVE Features=0x1<XSAVEOPT>
  VT-x: PAT,HLT,MTF,PAUSE,EPT,UG,VPID
  TSC: P-state invariant, performance statistics
real memory  = 17179869184 (16384 MB)
avail memory = 16439214080 (15677 MB)
Event timer "LAPIC" quality 600
ACPI APIC Table: <LENOVO TP-J9   >
FreeBSD/SMP: Multiprocessor System Detected: 4 CPUs
FreeBSD/SMP: 1 package(s) x 2 core(s) x 2 hardware threads
random: unblocking device.
Security policy loaded: MAC/ntpd (mac_ntpd)
ioapic0 <Version 2.0> irqs 0-23 on motherboard
Launching APs: 1 3 2
Timecounter "TSC-low" frequency 1247140210 Hz quality 1000
random: entropy device external interface
kbd1 at kbdmux0
module_register_init: MOD_LOAD (vesa, 0xffffffff80d41390, 0) error 19
[...]


[...]
dmesg|grep hda
hdac0: <Intel Haswell HDA Controller> mem 0xf1610000-0xf1613fff at
device 3.0 on pci0 hdac1: <Intel Lynx Point HDA Controller> mem
0xf1614000-0xf1617fff at device 27.0 on pci0 hdacc0: <Intel Haswell HDA
CODEC> at cad 0 on hdac0 hdaa0: <Intel Haswell Audio Function Group> at
CODEC> nid 1 on hdacc0
pcm0: <Intel Haswell (HDMI/DP 8ch)> at nid 3 on hdaa0
hdacc1: <Conexant CX20751/2 HDA CODEC> at cad 0 on hdac1
hdaa1: <Conexant CX20751/2 Audio Function Group> at nid 1 on hdacc1
pcm1: <Conexant CX20751/2 (Internal Analog Speaker)> at nid 23 on hdaa1
pcm2: <Conexant CX20751/2 (Right Analog Headphones)> at nid 22 on hdaa1
hdac0: Unexpected unsolicited response from address 0: 00000000
hdac0: Unexpected unsolicited response from address 0: 00000000
hdac0: Unexpected unsolicited response from address 0: 00000000
hdac0: Unexpected unsolicited response from address 0: 00000000