Hi Stefan,

>My guess is that Fox packages the .null. as the wrong type when it hands the value over to COM (the proper type to convert to can be determined from the TLB).

Well - i thought the NULL-Value should be the same as Nothing-Value in VB - here is the signature from the TLB :

[id(0x0000001a), helpstring("method BurnIsoAudioCD")]
void BurnIsoAudioCD(
[in] BSTR Artist,
[in] BSTR Title,
[in] VARIANT_BOOL CDExtra,
[in] INeroISOTrack* ISOTrack,
[in] INeroAudioTracks* AudioTracks,
[in] INeroCDStamp* CDStamp,
[in] NERO_BURN_FLAGS Flags,
[in] long Speed,
[in] NERO_MEDIA_TYPE type);

I guess I'll create an ActiveX in VB and resignate ...

Thanks a lot anyway...

Matthias