Indeed, on 17 November 1933 in Paris Modrakowska, accompanied by Léon Kartun on the piano, performed Mycielski’s Gorzka zatoka and Gdzieżeście (listed in the concert programme as Deux Mélodies). Also in 1933, on 25 March, Paris heard Mycielski’s Piano Trio. His Four Preludes for Cello and Piano, written for the brilliant French cellist Maurice Eisenberg, was performed in 1934 in Vilnius (by local musicians: Albert Katz and Samuel Chones), where, in the spring of that year, the composer began to work at the local station of the Polish Radio. 

Although Mycielski did not return to Poland for good until 1936, from 1933 he would spend quite long periods there and in 1934 he settled in Vilnius. He was welcomed there by Tadeusz Szeligowski, whom he had met earlier in Paris and who had invited him to work with him at the Polish Radio’s Vilnius station. Mycielski spent the following few months of that year in Vilnius, with a late spring break for a visit in Orniany, at the estate of Michał Tyszkiewicz (husband of popular singer, Hanka Ordonówna), where he composed Five Wedding Songs to words by Bruno Jasieński. While in Vilnius he also completed several other works, including the cello preludes. As part of his work for the radio, Mycielski would prepare various programmes, arrange music and with time also compose music of the radio theatre. He would write for newspapers and magazines increasingly frequently. According to Andrzej Szypuła, who has analysed a list compiled by the composer, in the inter-war period Mycielski’s articles appeared in Muzyka, Muzyka Polska, Gazeta Literacka, Conferencia, Pax, Zaułek, Kurier Wileński, Gazeta Artystów, Prosto z mostu, Arkady, Sprawy otwarte, Kurier Poranny, Muzyka współczesna, Ateneum (A. Szypuła, “Szkic do biografii Zygmunta Mycielskiego”, Kamerton 2012 no. 56). This demonstrates the breadth of Mycielski’s activity. He had liked writing since his childhood and now he was able to use it as an increasingly certain source of income. 

He returned to Paris, where he was elected President of the Association of Young Polish Musicians. On 31 January 1935 he organised a concert during which Maria Modrakowska sung his Five Wedding Songs for the first time (this time she was accompanied by Nadia Boulanger on the piano). The programme also featured works by other Polish composers: Antoni Szałowski, Tadeusz Szeligowski, Alfred Gradstein, Roman Maciejewski and Jerzy Fitelberg, as well as compositions by Mikołaj Zieleński and Claudio Monteverdi. Mycielski’s songs scored the biggest success and were appreciated by the French critics. 

Mycielski again went to Vilnius, but in the summer of 1937 he moved to Warsaw, where he became a regular music reviewer for Kurier Poranny. In the spring of 1938 he moved to Bukowina Tatrzańska, where he wanted to focus on creative work. But he did not compose much. Although he made a draft for a symphonic piece, the only work he completed was the song to Reiner Maria Rilke’s words Stimme eines jungen Bruders for soprano and piano. He was going through some spiritual dilemmas and wondered what to do next in life. However, all plans were put on hold by the outbreak of the Second World War.