ABBA were shown being interviewed in Swedish after one of their British concerts. 

In the same report concert-goers were asked for their comments along with New Musical Express journalist Bob Woffinden.

Rapport (Björn), 1971; 
Rapport (Frida), 1974;
Rapport, 1976; 
Rapport, 1977;
Rapport, 1978;
Rapport, 1979;
Rapport (Agnetha & Frida), 1981;
Rapport (Björn), 1982; 
Rapport (Agnetha), 1982;
Rapport (Benny & Björn), 1988; 
Rapport (Benny, Björn & Agnetha), 1995;
Rapport (Benny), 2004;
Rapport (Björn), 2007; 

Archive data from Swedish Media Database:

1977-02-13
Utgivning
År/datum 1977-02-13
Matrisnummer 70-76 1006
Anmärkningar
Speltid 30 min.
Exemplar
VHS T94-0094
Antal enheter 1
Ljud Stereo, färg
Arkivnummer T94-0094
MPEG-1 ZS_T94-0094
Filbeskrivning 1,5 Mbit/s, MPEG-1 layer 2, 48 kHz, 128 kbit/s
Arkivnummer ZS_T94-0094

Thanks to Julie Rickwood, Carl Magnus Palm, Uwe Meyer and Robin Andersson
YouTube link c/o Adrián León