An etv file extension is associated with the eTreppid audio file format.
ETV file extension - eTreppid audio data
What is etv file? How to open etv files?
File type specification:
The etv file extension is used for eTreppid Audio files playable with the eTplayer & ETVC media CODEC.
Seems to be obsolete file format without support from developer or producer.
This etv file type entry was marked as obsolete and no longer supported file format.
This type of file is no longer actively used and is most likely obsolete. This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types (like documents, projects etc.) that were replaced in higher versions of their original programs.