Regression: BSOD 0x1E during manual AC97 VBox driver installation from Rapps

For reproducing this, simply download AC97 VirtualBox driver from Rapps, extract it in C:\ReactOS and try to install it via Device Manager by selecting "Multimedia audio device".

Up to 0.4.13-dev-546-gf565083d589c93792ded2a7b28a40d99020efad2 it installs without any problems. Since 0.4.13-dev-547-g99fa38809fd8ed38d4d59fa1fcf3babb3216b895 once the installation starts, the system immediately crashes to BSOD 0x1e.
In debug mode, first appears an exception, and only after bt and cont, appears Fatal System Error 0x1e:



Entered debugger on last-chance exception (Exception Code: 0xc0000005) (Page Fault)

Memory at 0x00000048 could not be written: Page not present.

kdb:> bt

Eip:

<ntoskrnl.exe:15fd66 (sdk/lib/rtl/unicode.c:644 (RtlInitUnicodeString))>

Frames:

<portcls.sys:1433 (drivers/wdm/audio/backpln/portcls/adapter.cpp:275 (PcRegisterSubdevice))>

<ALCXWDM.SYS:14973>

<ALCXWDM.SYS:14b1c>

<portcls.sys:5a4e (drivers/wdm/audio/backpln/portcls/irp.cpp:98 (PortClsPnp))>

<portcls.sys:5c90 (drivers/wdm/audio/backpln/portcls/irp.cpp:450 (PcDispatchIrp))>

<ntoskrnl.exe:72580 (ntoskrnl/io/iomgr/irp.c:1286 (IofCallDriver))>

Couldn't access memory at 0xF6C7FA50!

kdb:> cont

*** Fatal System Error: 0x0000001e

                       (0xC0000005,0x8095FD66,0xF6C7F880,0x00000000)

Entered debugger on embedded INT3 at 0x0008:0x809554c4.

kdb:> 

There are many lines associated with portcls driver. After replacing portcls.sys on version from Win2k3, the installation completes succesfully even in 0.4.13-dev-547-g99fa388, without any failures. So problem is indeed only in our portcls driver.

P.S.: I could to install AC97 driver successfully only once in 0.4.13-dev-547-g99fa388 with our portcls only once, but after twice reboot appeared the same problem and the system couldn't boot into desktop.