Sony Xperia Z3 compact echo during calls with speaker

When I turn on the speaker, the other party can’t hear anything intelligible because of the echo. Looking at other posts on this forum, it seems like this is a bug in the software. Are there any fixes for it? I am using e-0.15-q-20210312105636-dev-z3c

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That is quite an old version. Later versions - which may fix the issue - are available for download at
https://images.ecloud.global/dev/z3c/
After installing e-0.17-q-20210530117214-dev-z3c.zip, you should find that future updates become available ‘Over the Air’ (OTA) using the Updater app