update NEWS, mention known issues
## New features
* Accept prefill credentials in base64 form #153 #811
- * Indroduce AAC encoder to audio redirection (requires Windows 10)
+ * Indroduce AAC encoder to audio redirection (requires Windows 10 client)
## Bugfixes
* Fix ocasional SEGV in drive redirection #838
* Add a PAM file for FreeBSD #824
* Several refactorings and cosmetic changes
+## Known issues
+ * Windows 10 (1703) shows black blank screen in RemoteFX mode
+ * This issue is already fixed at Insider Preview build 16273
+
# Release notes for xrdp v0.9.3.1 (2017/08/16)
This release fixes a trivial packaging issue #848 occurred in v0.9.3. The issue only affects systemd systems. This release is principally for distro packagers or users who compile & install xrdp from source.
