Lo explican en esa misma review que has puesto:

As so often, Tartan give us three soundtrack options: 5.1 mixes in Dolby Digital and DTS, plus an analogue 2.0 (Dolby Surround) option. DTS has the slight edge in clarity but there’s nothing very much in it. This isn’t a particularly adventurous soundtrack to begin with, pretty much front and centre throughout. The dialogue is a mix of English and Spanish: subtitles are provided for the Spanish dialogue, but for nothing else on the DVD – a frequent lapse for distributors like Tartan, who specialise in foreign-language material, when it comes to releasing English-language films like this.