Update: Removed several obsolete known bugs

known-bugs.txt

@@ -1,6 +1,6 @@
 OpenTTD's known bugs
 Last updated:    2018-11-05
-Release version: 1.8.0
+Release version: 1.9.0
 ------------------------------------------------------------------------
 
 
@@ -48,22 +48,6 @@ After a while of playing, colours get corrupted:
                 b) Switching off background slideshow
                 c) Setting up the 32bpp-anim or 32bpp-optimized blitter
 
-Long delay between switching songs/music:
-        On Windows there is a delay of a (few) second(s) between switching
-        of songs for the "Win32" driver. This delay is caused by the fact
-        that opening a MIDI file via MCI is extremely slow.
-
-        DirectMusic, known as "dmusic" in OpenTTD, has a much shorter delay.
-        However, under some circumstances DirectMusic does not reset its state
-        properly causing wrongly pitched/bad sounding songs. This problem is in
-        DirectMusic as it is reproducable with Microsoft's DirectMusic Producer.
-        DirectMusic has been deprecated since 2004 and as such has no support
-        for 64-bit OpenTTD.
-
-        As a delay is favourable over bad sounding music the "Win32" driver
-        is the default driver for OpenTTD. You can change this default by
-        setting the "musicdriver" in your openttd.cfg to "dmusic".
-
 Custom vehicle type name is incorrectly aligned:
         Some NewGRFs use sprites that are bigger than normal in the "buy
         vehicle" window. Due to this they have to encode an offset for
@@ -214,12 +198,6 @@ Train crashes entering same junction from block and path signals [#3928]:
         the train entering from path signal just after the backwards facing
         signal (from the path signal train) resolves the issue.
 
-Crashes when playing music [#3941]:
-        macOS's QuickTime (default music driver) and Windows' MCI ("Win32"
-        music driver) crash on some songs from OpenMSX. OpenTTD cannot do
-        anything about this. Please report these crashes to the authors
-        of OpenMSX so the crash causing songs can be removed or fixed.
-
 Crashes when run in a VM using Parallels Desktop [#4003]:
         When the Windows version of OpenTTD is executed in a VM under
         Parallels Desktop a privileged instruction exception may be thrown.
@@ -230,22 +208,6 @@ Crashes when run in a VM using Parallels Desktop [#4003]:
         lacking support for RDTSC calls. The problem can be avoided by using
         other VM-software, Wine, or running natively on macOS.
 
-OpenTTD hangs when started on 32-bit Windows [#4083]:
-        Under some circumstances OpenTTD might hang for hours on the
-        initialisation of the music driver. The exact circumstances are
-        unknown except that it is the "dmusic" music driver that has the
-        problem and that the "Win32" music driver does not. As a result
-        using the "Win32" music driver will work around this issue.
-
-        As the exact circumstances are unknown, and the obvious
-        configuration settings related to the music driver are at their
-        default we are not able to detect this failure, except when Windows'
-        music initialisation function returns after several hours and then
-        there is no point in switching the music driver anymore.
-        The reason we still use the "Win32" music driver as default are
-        described in the "Long delay between switching music/song" section
-        of this document.
-
 Entry- and exit signals are not dragged [#4378]:
         Unlike all other signal types, the entry- and exit signals are not
         dragged but instead normal signals are placed on subsequent track
@@ -265,14 +227,6 @@ Station build date is incorrect [#4415]:
         to "Date at which the last (re)construction took place" but this is
         deemed too specific and long for that window.
 
-Can't change volume inside OpenTTD [#4416]:
-        Some backends do not provide a means to change the volume of sound
-        effects or music. The mixing of music and sound is left to external
-        libraries/the operating system we can't handle the volume control
-        in OpenTTD. As a result you can't change the volume inside OpenTTD
-        for backends such as SDL; just use the volume control provided by
-        your operating system.
-
 (Temporary) wrong colours when switching to full screen [#4511]:
         On Windows it can happen that you temporarily see wrong colours
         when switching to full screen OpenTTD, either by starting