Problem loading several glb via GLTF.loader.parse

Questions
1

I have three *.glb.

I first convert them to blob files via

const blob = new Blob( [ response ] );

then I try to load them via

( blob as Blob ).arrayBuffer().then(

                ( buf ) => {

                    loader.parse( buf , '', ( gltf ) => {
                      ...

I get

Error: THREE.GLTFLoader: JSON content not found.
at new GLTFBinaryExtension (vendor.js:144728:13)
at GLTFLoader.parse (vendor.js:143976:52)
at main.js:1543:20
at ZoneDelegate.invoke (polyfills.js:381:26)
at Object.onInvoke (vendor.js:55934:33)
at ZoneDelegate.invoke (polyfills.js:380:52)
at Zone.run (polyfills.js:143:43)
at polyfills.js:1285:36
at ZoneDelegate.invokeTask (polyfills.js:415:31)
at Object.onInvokeTask (vendor.js:55921:33)

and for another one

RangeError: Offset is outside the bounds of the DataView
at DataView.getUint32 ()
at new GLTFBinaryExtension (vendor.js:144710:37)
at GLTFLoader.parse (vendor.js:143976:52)
at main.js:1543:20
at ZoneDelegate.invoke (polyfills.js:381:26)
at Object.onInvoke (vendor.js:55934:33)
at ZoneDelegate.invoke (polyfills.js:380:52)
at Zone.run (polyfills.js:143:43)
at polyfills.js:1285:36
at ZoneDelegate.invokeTask (polyfills.js:415:31)

any ideas why there’s a problem?

by the way it works fine when using loader.load but I want to avoid loading from my server and instead used the cached blob store in indexedDb.

Also here is the start og my glb as blob

glTF����JSON{“asset”:{“generator”:“Khronos glTF Blender I/O v1.5.17”,“version”:“2.0”},“scene”:0,“scenes”:[{“name”:“Scene”,“nodes”:[6,225]}],“nodes”:

Thanks in advance