InvalidOperationException: Sequence contains more than one element

[ther]

Sonarr version (exact version): 2.0.0.4323
Mono version (if Sonarr is not running on Windows): 4.4.2
OS: Ubuntu 14.04 Server
((Debug logs)): http://pastebin.com/v64DSy0Y
Description of issue: Log pretty much explains it. Trying to import ‘Dirty.Jobs.S05E11.Mattress.Recycler.720p.HDTV.DD5.1.x264-RZF’ with no success. Ends up saying:

[v2.0.0.4323] System.InvalidOperationException: Sequence contains more than one element
  at System.Linq.Enumerable.Single[TSource] (IEnumerable`1 source) <0x410adf20 + 0x00243> in <filename unknown>:0
  at NzbDrone.Core.Parser.Model.LocalEpisode.get_SeasonNumber () <0x410ad9c0 + 0x0010b> in <filename unknown>:0
  at NzbDrone.Core.Parser.Model.LocalEpisode.get_IsSpecial () <0x410ad920 + 0x0000f> in <filename unknown>:0
  at NzbDrone.Core.MediaFiles.EpisodeImport.Specifications.NotSampleSpecification.IsSatisfiedBy (NzbDrone.Core.Parser.Model.LocalEpisode localEpisode) <0x410ad810 + 0x00097> in <filename unknown>:0
  at NzbDrone.Core.MediaFiles.EpisodeImport.ImportDecisionMaker.EvaluateSpec (IImportDecisionEngineSpecification spec, NzbDrone.Core.Parser.Model.LocalEpisode localEpisode) <0x410a1460 + 0x0004b> in <filename unknown>:0

[markus101]

The error indicates that there are multiple episodes across multiple seasons that causes Sonarr to see two different seasons when there is only one.

I don’t see any issues with the release name and it doesn’t seem to be an issue with a mapping from thexem.de.
Please refresh that series in Sonarr and advise if the issue persists.