diff --git a/packages/alphatab/src/importer/alphaTex/AlphaTex1LanguageHandler.ts b/packages/alphatab/src/importer/alphaTex/AlphaTex1LanguageHandler.ts
index 0bd5ab102..504750b46 100644
--- a/packages/alphatab/src/importer/alphaTex/AlphaTex1LanguageHandler.ts
+++ b/packages/alphatab/src/importer/alphaTex/AlphaTex1LanguageHandler.ts
@@ -1708,7 +1708,7 @@ export class AlphaTex1LanguageHandler implements IAlphaTexLanguageImportHandler
                 let tbi = 0;
                 let typeAndStyle = true;
                 let typeSet = false;
-                while (typeAndStyle) {
+                while (typeAndStyle && tbi < (p.arguments?.arguments.length ?? 0)) {
                     switch (p.arguments!.arguments[tbi].nodeType) {
                         case AlphaTexNodeType.Ident:
                         case AlphaTexNodeType.String:
@@ -2141,7 +2141,7 @@ export class AlphaTex1LanguageHandler implements IAlphaTexLanguageImportHandler
 
                 let typeAndStyle = true;
                 let typeSet = false;
-                while (typeAndStyle) {
+                while (typeAndStyle && tbi < (p.arguments?.arguments.length ?? 0)) {
                     switch (p.arguments!.arguments[tbi].nodeType) {
                         case AlphaTexNodeType.Ident:
                         case AlphaTexNodeType.String:
@@ -2411,9 +2411,13 @@ export class AlphaTex1LanguageHandler implements IAlphaTexLanguageImportHandler
         argStartIndex: number,
         exact: boolean
     ): BendPoint[] | undefined {
-        let args = p.arguments!.arguments;
+        if (!p.arguments) {
+            return undefined;
+        }
+
+        let args = p.arguments.arguments;
         let remainingArgs = args.length - argStartIndex;
-        let errorNode: AlphaTexAstNode = p.arguments!;
+        let errorNode: AlphaTexAstNode = p.arguments;
 
         // unwrap value list
         if (remainingArgs > 0 && args[argStartIndex].nodeType === AlphaTexNodeType.Arguments) {
diff --git a/packages/alphatab/test/importer/__snapshots__/AlphaTexImporter.test.ts.snap b/packages/alphatab/test/importer/__snapshots__/AlphaTexImporter.test.ts.snap
index 26a102a43..806c9aaf2 100644
--- a/packages/alphatab/test/importer/__snapshots__/AlphaTexImporter.test.ts.snap
+++ b/packages/alphatab/test/importer/__snapshots__/AlphaTexImporter.test.ts.snap
@@ -6033,13 +6033,39 @@ exports[`AlphaTexImporterTest > errors > at219 > bendstyle > lexer-diagnostics 1
 
 exports[`AlphaTexImporterTest > errors > at219 > bendstyle > parser-diagnostics 1`] = `[]`;
 
-exports[`AlphaTexImporterTest > errors > at219 > bendstyle > semantic-diagnostics 1`] = `[]`;
+exports[`AlphaTexImporterTest > errors > at219 > bendstyle > semantic-diagnostics 1`] = `
+[
+  Map {
+    "code" => 212,
+    "severity" => 2,
+    "message" => "Unrecogized property 'invalid', expected one of nh,ah,th,ph,sh,fh,v,vw,sl,ss,sib,sia,sou,sod,psu,psd,h,lht,g,ac,hac,ten,tr,pm,st,lr,x,t,turn,iturn,umordent,lmordent,string,hide,b,be,lf,rf,acc,slur,-,f,fo,vs,v,vw,s,p,tt,d,dd,su,sd,cre,dec,spd,sph,spu,spe,slashed,ds,glpf,glpt,waho,wahc,legatoorigin,timer,tu,txt,lyrics,tb,tbe,bu,bd,au,ad,ch,gr,dy,tempo,volume,balance,tp,barre,rasg,ot,instrument,bank,fermata,beam,restdisplaypitch",
+    "start" => Map {
+      "col" => 25,
+      "line" => 1,
+      "offset" => 24,
+    },
+  },
+]
+`;
 
 exports[`AlphaTexImporterTest > errors > at219 > bendtype > lexer-diagnostics 1`] = `[]`;
 
 exports[`AlphaTexImporterTest > errors > at219 > bendtype > parser-diagnostics 1`] = `[]`;
 
-exports[`AlphaTexImporterTest > errors > at219 > bendtype > semantic-diagnostics 1`] = `[]`;
+exports[`AlphaTexImporterTest > errors > at219 > bendtype > semantic-diagnostics 1`] = `
+[
+  Map {
+    "code" => 212,
+    "severity" => 2,
+    "message" => "Unrecogized property 'invalid', expected one of nh,ah,th,ph,sh,fh,v,vw,sl,ss,sib,sia,sou,sod,psu,psd,h,lht,g,ac,hac,ten,tr,pm,st,lr,x,t,turn,iturn,umordent,lmordent,string,hide,b,be,lf,rf,acc,slur,-,f,fo,vs,v,vw,s,p,tt,d,dd,su,sd,cre,dec,spd,sph,spu,spe,slashed,ds,glpf,glpt,waho,wahc,legatoorigin,timer,tu,txt,lyrics,tb,tbe,bu,bd,au,ad,ch,gr,dy,tempo,volume,balance,tp,barre,rasg,ot,instrument,bank,fermata,beam,restdisplaypitch",
+    "start" => Map {
+      "col" => 20,
+      "line" => 1,
+      "offset" => 19,
+    },
+  },
+]
+`;
 
 exports[`AlphaTexImporterTest > errors > at219 > bracketextendmode > lexer-diagnostics 1`] = `[]`;
 
@@ -6379,7 +6405,20 @@ exports[`AlphaTexImporterTest > errors > at219 > whammybartype > lexer-diagnosti
 
 exports[`AlphaTexImporterTest > errors > at219 > whammybartype > parser-diagnostics 1`] = `[]`;
 
-exports[`AlphaTexImporterTest > errors > at219 > whammybartype > semantic-diagnostics 1`] = `[]`;
+exports[`AlphaTexImporterTest > errors > at219 > whammybartype > semantic-diagnostics 1`] = `
+[
+  Map {
+    "code" => 212,
+    "severity" => 2,
+    "message" => "Unrecogized property 'invalid', expected one of nh,ah,th,ph,sh,fh,v,vw,sl,ss,sib,sia,sou,sod,psu,psd,h,lht,g,ac,hac,ten,tr,pm,st,lr,x,t,turn,iturn,umordent,lmordent,string,hide,b,be,lf,rf,acc,slur,-,f,fo,vs,v,vw,s,p,tt,d,dd,su,sd,cre,dec,spd,sph,spu,spe,slashed,ds,glpf,glpt,waho,wahc,legatoorigin,timer,tu,txt,lyrics,tb,tbe,bu,bd,au,ad,ch,gr,dy,tempo,volume,balance,tp,barre,rasg,ot,instrument,bank,fermata,beam,restdisplaypitch",
+    "start" => Map {
+      "col" => 21,
+      "line" => 1,
+      "offset" => 20,
+    },
+  },
+]
+`;
 
 exports[`AlphaTexImporterTest > sync 1`] = `
 Map {