[ltp] x250: Intel Rapid Start works but has quirks

[D.T.]

Hello everyone,
recently I purchased a Thinkpad x250.
It has a 256GB SSD.

Intel Rapid Start (IRS) works as it should:

    I created the required partition, exactly 8GB in size like my RAM
and swap
    in BIOS, I set it to activate immediately.
    On the operating system level, I have disabled hibernation
completely, everything goes to suspend, from where the BIOS takes over
and sends the machine into hibernation in less than a minute.
    Opening the lid or pressing the power button wakes the machine up
again (boot logo reads "Resuming from deep sleep") (*).

The Problems I noticed:

    I have sound after resuming, but the headphone plug doesn't, i.e. I
cannot use external Speakers or headphones. This is happening with both
pulseaudio and pure ALSA.
    In BIOS I have set The primary function for the F* keys to be F1 -
F12, but after a resume this goes back to function keys, which was the
default BIOS setting when I got the machine
    (*) In some situations - I think when the system goes to sleep
because of low battery - the IRS hibernation does not take, i.e. the
system remains in Suspend state. This part I have not fully researched
yet.

What I did to make sure the problem is NOT independent of IRS:

    tried various distros, mostly ArchLinux and Debian based - the
problems always occur as described above
    disabled IRS - I have full sound after resuming from Suspend and
the Fn primary fiunction is as set in BIOS
    enabled Linux' own hibernation - I have full sound after resuming
from Hibernate and the Fn primary fiunction is as set in BIOS

Other info:

    I flashed the BIOS to version 1.38 when I got the machine.

Is it possible to fix this?
Is this a known problem?
Could it be this has nothing to do with the operating system?

Of course I could just use Linux' own hibernation, but with IRS I can
save a few seconds when waking up.

I'll be thankful for any input you can give!

o.

PS:
I have never used Windows on this machine and it isn't installed
anymore.