ConfuserEx: [Bug] Same key has already been added

Trying to run confuser against my project and some of the class libraries that it builds and get the following error:

[INFO] Initializing… [DEBUG] Building pipeline… [INFO] Resolving dependencies… [DEBUG] Checking Strong Name… [WARN] [EntityFramework.dll] SN Key is not provided for a signed module, the output may not be working. [DEBUG] Creating global .cctors… [DEBUG] Watermarking… [DEBUG] Executing ‘Name analysis’ phase… [DEBUG] Building VTables & identifier list… [ERROR] Unknown error occurred. Exception: System.ArgumentException: An item with the same key has already been added. at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource) at System.Collections.Generic.Dictionary2.Insert(TKey key, TValue value, Boolean add) at System.Linq.Enumerable.ToDictionary[TSource,TKey,TElement](IEnumerable1 source, Func2 keySelector, Func2 elementSelector, IEqualityComparer1 comparer) at Confuser.Renamer.VTable.Implements(VTableConstruction vTbl, Dictionary2 virtualMethods, VTable ifaceVTbl, TypeSig iface) at Confuser.Renamer.VTable.ConstructVTable(TypeDef typeDef, VTableStorage storage) at Confuser.Renamer.VTableStorage.GetOrConstruct(TypeDef type) at Confuser.Renamer.AnalyzePhase.Execute(ConfuserContext context, ProtectionParameters parameters) at Confuser.Core.ProtectionPipeline.ExecuteStage(PipelineStage stage, Action1 func, Func1 targets, ConfuserContext context) at Confuser.Core.ConfuserEngine.RunPipeline(ProtectionPipeline pipeline, ConfuserContext context) at Confuser.Core.ConfuserEngine.RunInternal(ConfuserParameters parameters, CancellationToken token) Failed at 11:10, 0:04 elapsed.