Many young children are missing out on decent music education because teachers often have little experience or training in the subject, research suggests.
The new study raises concerns about the differences between schools - with some youngsters receiving just 20 minutes of music instruction a week and others getting up to 70 minutes.
It also suggests that schools are suffering from a lack of musical instruments.
The report, commissioned by the EMI Music Sound Foundation, an independent charity, is based on a small-scale survey of teachers at 132 primaries and 28 secondary schools taking part in a music training exercise and a separate poll of the headteachers at the primaries involved in the project.
The findings show that half of the teachers questioned said they did not play an instrument or sing, while 45% said they could not read music.
And a third (33%) said their previous musical experiences were not at all relevant to their work as an infant school teacher.
The amount of music training the teachers said they had received as part of their initial teaching training ranged from one to 20 days, with more than half (55%) saying it had been limited to a single day.
And many raised concerns about the quality of that training, with more than a third (39%) saying it did not help them in meeting the requirements of the national curriculum.
Professor Sue Hallam from the Institute of Education, which conducted the study, said: "There is wide variability in the quality of the teaching and the standards attained by the pupils.
"The best lessons are delivered by the music co-ordinators who are either very experienced musicians or very confident. However, almost four in 10 of the heads we interviewed said they did not have a music specialist."