ACF PRO Error when I public post

Every time I save an article with a repetear field (also if it’s qTranslate specific field), the page return this error.

I have:
ACF PRO version 5.2.3
qTranslate-X version 3.3
ACF qTranslate version 1.7.6

Warning: Illegal string offset 'field_5548b2b971eab' in /Users/cr/wp-content/plugins/qtranslate-x/admin/qtx_configuration.php on line 37

Warning: Illegal string offset 'en' in /Users/cr/wp-content/plugins/qtranslate-x/admin/qtx_configuration.php on line 37

Warning: Illegal string offset 'it' in /Users/cr/wp-content/plugins/qtranslate-x/admin/qtx_configuration.php on line 37

Warning: Cannot modify header information - headers already sent by (output started at /Users/cr/wp-content/plugins/qtranslate-x/admin/qtx_configuration.php:37) in /Users/cr/wp-includes/pluggable.php on line 1196

Can someone please help me?

https://wordpress.org/plugins/acf-qtranslate/