While the rest of Europe went to war, life continued relatively normally for the Busches and Serkins in neutral Switzerland, although it seemed far from certain that Hitler would respect that neutrality and refrain from invading. Frieda, chafing at the compromises she felt the Swiss were making with their Nazi neighbours, fired off a letter to Werner Reinhart in which she complained about the engagement of Furtwängler to conduct in Winterthur and the willingness of the Winterthur City Orchestra to continue giving concerts in Konstanz, on the German side of the border – and incidentally chided Reinhart for not supporting the Lucerne Festival. After an interval Reinhart wrote a seven-page rejoinder, setting out the Swiss policy of neutrality in music, as in other things, and questioning the validity of excluding artists such as Walter Gieseking from the Lucerne event on purely political grounds. Much of September was spent by the Busch party at the little village of Eriz near Thun, where the reality of the international situation could be held at bay for a few weeks. Joseph Segal, who stayed with his mother in the same small three-storey house as the Serkins, found that he was expected to have his violin lessons upstairs, while Serkin practised thunderously downstairs. ‘Play forte!’ was the riposte from Busch, who rode up the hill on a bicycle from his own holiday home for the lessons. ‘He would come in, panting very hard – he was quite a heavy man – and take his working violin straight out of its case’, Segal remembered. ‘He would play with me a bit here and there.’

This talented pupil, born in Haifa of Russian parents, came with the recommendation of Sir Adrian Boult, who rehearsed the Beethoven Concerto with Segal and the BBC Symphony Orchestra as part of the first prize that the then fourteen-year-old won in the 1938 British Empire Violin Competition. Busch relented in his opposition to teaching prodigies because he was so taken with Segal's father Levi – who was still based in Palestine most of the time, while Joseph was accompanied abroad by his equally pleasant mother, Yaffa.