Scanning issues and log error messages

I'm fairly sure there's something wrong with my LMS but don't know where to start. Scan for new and changed music used to take about 90 seconds after I'd added a few new albums, but now it takes about 8 minutes even with no new items, and after the scan has finished LMS is unresponsive for several more minutes and shows 100% CPU usage.

I also can't work out how to attach part of my log, so I've pasted into this post.

Are the messages in the log related to my problems, and if not where do I start to troubleshoot this?

Logitech Media Server Version: 7.8.0 - 1391769631 @ Sat Feb 8 03:04:49 CUT 2014
Hostname: Sonata
Server IP Address: 192.168.0.50
Server HTTP Port Number: 9000
Operating system: Windows 7 - EN - cp1252
Platform Architecture: 8664
Perl Version: 5.14.1 - MSWin32-x86-multi-thread
Database Version: DBD::SQLite 1.34_01 (sqlite 3.7.7.1)
Total Players Recognized: 3


[14-02-09 17:01:21.2280] Slim::Music::Artwork::updateStandaloneArtwork (204) Starting updateStandaloneArtwork for 630 albums
[14-02-09 17:01:23.5497] Slim::Schema::Storage::throw_exception (122) Error: DBI Exception: DBD::SQLite::st execute failed: database table is locked [for Statement "drop table temp_track_statistics"]
[14-02-09 17:01:23.5501] Slim::Schema::Storage::throw_exception (122) Backtrace:

frame 0: Slim::Utils::Log::logBacktrace (/<C:\PROGRA~2\SQUEEZ~1\server\SQUEEZ~3.EXE>Slim/Schema/Storage.pm line 122)
frame 1: Slim::Schema::Storage::throw_exception (/<C:\PROGRA~2\SQUEEZ~1\server\SQUEEZ~3.EXE>DBIx/Class/Storage/DBI.pm line 1006)
frame 2: DBIx::Class::Storage::DBI::__ANON__ (C:\ProgramData\Squeezebox\Cache\InstalledPlugins/Plugins/TrackStat/Storage.pm line 1354)
frame 3: (eval) (C:\ProgramData\Squeezebox\Cache\InstalledPlugins/Plugins/TrackStat/Storage.pm line 1353)
frame 4: Plugins::TrackStat::Storage::refreshTracks (C:\ProgramData\Squeezebox\Cache\InstalledPlugins/Plugins/TrackStat/Plugin.pm line 4165)
frame 5: Plugins::TrackStat::Plugin::commandCallback65 (/<C:\PROGRA~2\SQUEEZ~1\server\SQUEEZ~3.EXE>Slim/Control/Request.pm line 2081)
frame 6: (eval) (/<C:\PROGRA~2\SQUEEZ~1\server\SQUEEZ~3.EXE>Slim/Control/Request.pm line 2081)
frame 7: Slim::Control::Request::notify (/<C:\PROGRA~2\SQUEEZ~1\server\SQUEEZ~3.EXE>Slim/Control/Request.pm line 859)
frame 8: Slim::Control::Request::checkNotifications (slimserver.pl line 690)
frame 9: main::idle (slimserver.pl line 659)
frame 10: main::main (slimserver.pl line 103)
frame 11: PerlSvc::Interactive (/<C:\PROGRA~2\SQUEEZ~1\server\SQUEEZ~3.EXE>PerlSvc. pm line 99)
frame 12: PerlSvc::_interactive (slimserver.pl line 0)
frame 13: (eval) (slimserver.pl line 0)

[14-02-09 17:05:17.5470] Slim::Schema::Storage::throw_exception (122) Error: DBI Exception: DBD::SQLite::db create_function failed: sqlite_create_function failed with error unable to delete/modify user-function due to active statements
[14-02-09 17:05:17.5473] Slim::Schema::Storage::throw_exception (122) Backtrace:

frame 0: Slim::Utils::Log::logBacktrace (/<C:\PROGRA~2\SQUEEZ~1\server\SQUEEZ~3.EXE>Slim/Schema/Storage.pm line 122)
frame 1: Slim::Schema::Storage::throw_exception (/<C:\PROGRA~2\SQUEEZ~1\server\SQUEEZ~3.EXE>DBIx/Class/Storage/DBI.pm line 1006)
frame 2: DBIx::Class::Storage::DBI::__ANON__ (C:\ProgramData\Squeezebox\Cache\InstalledPlugins/Plugins/SQLPlayList/Plugin.pm line 232)
frame 3: Plugins::SQLPlayList::Plugin::createSQLiteFunction s (C:\ProgramData\Squeezebox\Cache\InstalledPlugins/Plugins/SQLPlayList/Plugin.pm line 211)
frame 4: Plugins::SQLPlayList::Plugin::__ANON__ (/<C:\PROGRA~2\SQUEEZ~1\server\SQUEEZ~3.EXE>Slim/Control/Request.pm line 2081)
frame 5: (eval) (/<C:\PROGRA~2\SQUEEZ~1\server\SQUEEZ~3.EXE>Slim/Control/Request.pm line 2081)
frame 6: Slim::Control::Request::notify (/<C:\PROGRA~2\SQUEEZ~1\server\SQUEEZ~3.EXE>Slim/Control/Request.pm line 859)
frame 7: Slim::Control::Request::checkNotifications (slimserver.pl line 690)
frame 8: main::idle (slimserver.pl line 659)
frame 9: main::main (slimserver.pl line 103)
frame 10: PerlSvc::Interactive (/<C:\PROGRA~2\SQUEEZ~1\server\SQUEEZ~3.EXE>PerlSvc. pm line 99)
frame 11: PerlSvc::_interactive (slimserver.pl line 0)
frame 12: (eval) (slimserver.pl line 0)