I experienced the same behavior since a few days. Reverting to the previous update version did not help. I am on Arch (x86) and my mono version is:
mono --version
Mono JIT compiler version 5.0.0 (Stable 5.0.0.100/9667aa6 Fri May 12 07:20:13 UTC 2017)
Copyright (C) 2002-2014 Novell, Inc, Xamarin Inc and Contributors. www.mono-project.com
TLS: __thread
SIGSEGV: altstack
Notifications: epoll
Architecture: amd64
Disabled: none
Misc: softdebug
LLVM: supported, not enabled.
GC: sgen (concurrent by default)
My config.xml:
> <Config>
> <LogLevel>Debug</LogLevel>
> <Port>8989</Port>
> <UrlBase>/nzbdrone</UrlBase>
> <BindAddress>*</BindAddress>
> <SslPort>9898</SslPort>
> <EnableSsl>False</EnableSsl>
> <ApiKey>XXXXXXXXXXXXXXXX</ApiKey>
> <AuthenticationMethod>Basic</AuthenticationMethod>
> <Branch>master</Branch>
> <LaunchBrowser>True</LaunchBrowser>
> <SslCertHash></SslCertHash>
> <UpdateMechanism>BuiltIn</UpdateMechanism>
> <UpdateAutomatically>True</UpdateAutomatically>
> </Config>
logs: (with debug enabled, s. above):
17-6-12 12:32:26.0|Info|Bootstrap|Starting Sonarr - /opt/sonarr/NzbDrone.exe - Version 2.0.0.4753
17-6-12 12:32:34.2|Info|MigrationLogger|*** Migrating data source=/home/xxx/.config/NzbDrone/nzbdrone.db;cache size=-10485760;datetimekind=Utc;journal mode=Wal;pooling=True;version=3 ***
17-6-12 12:32:34.8|Info|MigrationLogger|*** Migrating data source=/home/xxx/.config/NzbDrone/logs.db;cache size=-10485760;datetimekind=Utc;journal mode=Wal;pooling=True;version=3 ***
17-6-12 12:32:35.1|Info|Router|Application mode: Interactive
17-6-12 12:32:35.1|Info|OwinHostController|Listening on the following URLs:
17-6-12 12:32:35.1|Info|OwinHostController| http://:8989/nzbdrone/
17-6-12 12:32:35.1|Info|OwinHostController| http://:8989/
17-6-12 12:32:35.8|Info|NancyBootstrapper|Starting Web Server
17-6-12 12:33:12.9|Info|RssSyncService|Starting RSS Sync
17-6-12 12:33:13.1|Warn|FetchAndParseRssService|No available indexers. check your configuration.
17-6-12 12:33:13.1|Info|DownloadDecisionMaker|No results found
17-6-12 12:33:13.1|Info|RssSyncService|RSS Sync Completed. Reports found: 0, Reports grabbed: 0
17-6-12 12:34:22.5|Info|Bootstrap|Starting Sonarr - /opt/sonarr/NzbDrone.exe - Version 2.0.0.4748
17-6-12 12:34:30.5|Info|MigrationLogger|*** Migrating data source=/home/xxx/.config/NzbDrone/nzbdrone.db;cache size=-10485760;datetimekind=Utc;journal mode=Wal;pooling=True;version=3 ***
17-6-12 12:34:31.1|Info|MigrationLogger|*** Migrating data source=/home/xxxr/.config/NzbDrone/logs.db;cache size=-10485760;datetimekind=Utc;journal mode=Wal;pooling=True;version=3 ***
17-6-12 12:34:31.5|Info|Router|Application mode: Interactive
17-6-12 12:34:31.5|Info|OwinHostController|Listening on the following URLs:
17-6-12 12:34:31.5|Info|OwinHostController| http://:8989/nzbdrone/
17-6-12 12:34:31.5|Info|OwinHostController| http://:8989/
17-6-12 12:34:32.1|Info|NancyBootstrapper|Starting Web Server
17-6-12 12:35:03.8|Info|Bootstrap|Starting Sonarr - /opt/sonarr/NzbDrone.exe - Version 2.0.0.4748
17-6-12 12:35:12.4|Info|MigrationLogger|*** Migrating data source=/home/xxxr/.config/NzbDrone/nzbdrone.db;cache size=-10485760;datetimekind=Utc;journal mode=Wal;pooling=True;version=3 ***
17-6-12 12:35:13.0|Info|MigrationLogger|*** Migrating data source=/home/xxx/.config/NzbDrone/logs.db;cache size=-10485760;datetimekind=Utc;journal mode=Wal;pooling=True;version=3 ***
17-6-12 12:35:13.3|Info|Router|Application mode: Interactive
17-6-12 12:35:13.3|Info|OwinHostController|Listening on the following URLs:
17-6-12 12:35:13.3|Info|OwinHostController| http://:8989/nzbdrone/
17-6-12 12:35:13.3|Info|OwinHostController| http://:8989/
17-6-12 12:35:14.0|Info|NancyBootstrapper|Starting Web Server