Small additionals: after upgrading to "Linux zx386 5.4.0-58-generic #64-Ubuntu SMP Wed Dec 9 08:16:25 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux" where "linux-firmware" was upgraded to 1.187.6 version resolved the issue. In that package, sof-firmware was upgraded to 1.6 with current issue fixes.
Small additionals: after upgrading to "Linux zx386 5.4.0-58-generic #64-Ubuntu SMP Wed Dec 9 08:16:25 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux" where "linux-firmware" was upgraded to 1.187.6 version resolved the issue. In that package, sof-firmware was upgraded to 1.6 with current issue fixes.
Thank you all for helping solve this issue