Composers at their best in Chamber Music?

[eschiss1]

He actually lived to a ripe old age of 85, dying in 1933. However, he had to stop composing in 1885 at the young age of 37 due to a brain condition known as neurasthenia, which rendered Duparc incapable ofcomposing anything ever again (tragic!). He was not a prolific composer during these early years and so left only a few works, nearly entirely songs. The only chamber music he left was a Flute Sonata.

?
Duparc apparently left a cello sonata from 1867 that's been recorded, and some orchestral music (a work inspired by Lenore, for example) in addition to his songs, but not much in all, agreed. Did not know there was also a flute sonata too.
Eric