Non-Admin Unable to Upload Assets

I have quite a big problem.

I've just finished my second perch site and for the second time, my clients have been unable to upload assets.

In both cases, when the non-admin user (editor) uploads an asset, nothing happens after the upload and no file appears. This can be fixed by giving the user an Admin role. I don't think this is normal behaviour?

Perch: 3.1.2
Production mode: Production (100)
Installed apps: content (3.1.2), assets (3.1.2), categories (3.1.2), perch_forms (1.12)
DB driver: PDO
DB tables: perch3_categories (0), perch3_category_counts (0), perch3_category_sets (0), perch3_content_index (966), perch3_content_items (283), perch3_content_regions (48), perch3_forms (2), perch3_forms_responses (2), perch3_gallery_albums (1), perch3_gallery_image_versions (108), perch3_gallery_images (18), perch3_menu_items (10), perch3_navigation (0), perch3_navigation_pages (0), perch3_page_templates (1), perch3_pages (7), perch3_resource_log (546), perch3_resource_tags (0), perch3_resources (107), perch3_resources_to_tags (0), perch3_settings (21), perch3_user_passwords (0), perch3_user_privileges (35), perch3_user_role_privileges (2), perch3_user_roles (2), perch3_users (2)
Users: 2
App runtimes:
<?php
    $apps_list = [
    'perch_forms'
    ];
Editor plug-ins:
H1: 5ea6933780be8b0887ae4a7ca3b67fe4
L1: 05f6dadc37b49209b05774f08c65450f
F1: 3b606135b33e6a102526838f4152a807
headerColour: #ffffff
content_singlePageEdit: 1
helpURL:
siteURL: /
hideBranding: 1
content_collapseList: 1
lang: en-gb
installedAt: 3.1.2
update_3.1.2: done
latest_version:
on_sale_version: 3.1.3
perch_gallery_update: 2.8.5
headerScheme: light
dashboard: 1
sidebar_back_link: 0
hide_pwd_reset: 0
keyboardShortcuts: 0
content_hideNonEditableRegions: 0
content_frontend_edit: 0
content_skip_region_list: 0
assets_restrict_buckets: 0
PERCH_DEVELOPMENT: 10
PERCH_STAGING: 50
PERCH_PRODUCTION: 100
PERCH_DB_PREFIX: perch3_
PERCH_TZ: UTC
PERCH_LOGINPATH: /modulizer
PERCH_PATH: /home/linweb37/c/cafecentralpark.com-1099403400/user/htdocs/modulizer
PERCH_CORE: /home/linweb37/c/cafecentralpark.com-1099403400/user/htdocs/modulizer/core
PERCH_RESFILEPATH: /home/linweb37/c/cafecentralpark.com-1099403400/user/htdocs/modulizer/resources
PERCH_RESPATH: /modulizer/resources
PERCH_HTML5: 1
PERCH_RUNWAY:
PERCH_ERROR_MODE: DIE
PERCH_DATE_LONG: %d %B %Y
PERCH_DATE_SHORT: %d %b %Y
PERCH_TIME_SHORT: %H:%M
PERCH_TIME_LONG: %H:%M:%S
PERCH_RUNWAY_ROUTED:
PERCH_STRONG_PASSWORDS:
PERCH_ASSET_VERSION: 6738d5d5f5664f7c5e34
PERCH_DEBUG:
PERCH_PREVIEW_ARG: preview
PERCH_TEMPLATE_PATH: /home/linweb37/c/cafecentralpark.com-1099403400/user/htdocs/modulizer/templates
PERCH_TEMPLATE_FILTERS:
PERCH_DEFAULT_DOC: index.php
PERCH_DEFAULT_EXT: .php
PERCH_PRODUCTION_MODE: 100
PERCH_XHTML_MARKUP:
PERCH_RWD: 1
PERCH_HTML_ENTITIES:
PERCH_SSL:
PERCH_STRIPSLASHES:
PERCH_PROGRESSIVE_FLUSH: 1
PERCH_PARANOID:
PERCH_FORCE_SECURE_COOKIES:
PERCH_DEFAULT_BUCKET: default
PERCH_TRANSLATION_ASSIST:
PERCH_PASSWORD_MIN_LENGTH: 6
PERCH_MAX_FAILED_LOGINS: 10
PERCH_AUTH_LOCKOUT_DURATION: 1 HOUR
PERCH_VERIFY_UPLOADS:
PERCH_PRIV_ASSIST:
PERCH_CUSTOM_EDITOR_CONFIGS:
PERCH_ENABLE_EXIF: 1
PERCH_AUTH_PLUGIN:
PERCH_DB_CHARSET: utf8
PERCH_DB_PORT:
PERCH_DB_SOCKET:
PERCH_APPS_EDITOR_PLUGIN: markitup
PERCH_APPS_EDITOR_MARKUP_LANGUAGE: markdown

PHP: 7.2.12
Zend: 3.2.0
OS: Linux
SAPI: cgi-fcgi
Safe mode: not detected
MySQL client: 5.5.60-MariaDB
MySQL server: 5.6.42-log
Free disk space: 122.41 GB
Extensions: Core, date, libxml, openssl, pcre, sqlite3, zlib, bz2, calendar, ctype, curl, hash, fileinfo, filter, ftp, gettext, gmp, SPL, iconv, intl, pcntl, session, standard, posix, readline, Reflection, Phar, shmop, SimpleXML, sockets, mbstring, sysvmsg, sysvsem, sysvshm, tokenizer, wddx, xml, cgi-fcgi, bcmath, dba, dom, gd, igbinary, imap, json, ldap, exif, mysqli, odbc, PDO, pdo_dblib, pdo_mysql, PDO_ODBC, pdo_pgsql, pdo_sqlite, pgsql, pspell, snmp, soap, tidy, xmlreader, xmlrpc, xmlwriter, xsl, zip, ionCube Loader
GD: Yes
ImageMagick: No
PHP max upload size: 20M
PHP max form post size: 20M
PHP memory limit: 64M
Total max uploadable file size: 20M
Resource folder writeable: Yes
Session timeout: 24 minutes
Native JSON: Yes
Filter functions: Yes
Transliteration functions: Yes
PATH: /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin
PWD: /var/www/fcgi
PHP_FCGI_MAX_REQUESTS: 100
ORIG_SCRIPT_NAME: /fcgi-bin/php72-cgi
ORIG_PATH_TRANSLATED: /home/linweb37/c/cafecentralpark.com-1099403400/user/htdocs/modulizer/core/settings/diagnostics/index.php
ORIG_PATH_INFO: /modulizer/core/settings/diagnostics/index.php
ORIG_SCRIPT_FILENAME: /var/www/fcgi/php72-cgi
SCRIPT_NAME: /modulizer/core/settings/diagnostics/index.php
REQUEST_URI: /modulizer/core/settings/diagnostics/?extended
QUERY_STRING: extended
REQUEST_METHOD: GET
SERVER_PROTOCOL: HTTP/1.0
GATEWAY_INTERFACE: CGI/1.1
REDIRECT_URL: /modulizer/core/settings/diagnostics/index.php
REDIRECT_QUERY_STRING: extended
REMOTE_PORT: 44994
SCRIPT_FILENAME: /home/linweb37/c/cafecentralpark.com-1099403400/user/htdocs/modulizer/core/settings/diagnostics/index.php
SERVER_ADMIN: support@fasthosts.com
CONTEXT_DOCUMENT_ROOT: /var/www/fcgi/
CONTEXT_PREFIX: /fcgi-bin/
REQUEST_SCHEME: http
DOCUMENT_ROOT: /home/linweb37/c/cafecentralpark.com-1099403400/user/htdocs
REMOTE_ADDR: 80.7.192.7
SERVER_PORT: 80
SERVER_ADDR: 127.0.0.1
SERVER_NAME: 1099452403.1070340810.temp.prositehosting.co.uk
SERVER_SOFTWARE: Apache
HTTP_COOKIE: __utmz=257995146.1542090971.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none); cmsa=1; __utmc=257995146; __utma=257995146.1141620834.1542090971.1542215003.1542224377.5; PHPSESSID=63b58edbcb926016b9e7c18bc918525c
HTTP_ACCEPT_LANGUAGE: en-US,en;q=0.9,it;q=0.8,fr;q=0.7
HTTP_ACCEPT_ENCODING: gzip, deflate
HTTP_REFERER: https://1099452403.1070340810.temp.prositehosting.co.uk/modulizer/core/settings/diagnostics/
HTTP_ACCEPT: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8
HTTP_USER_AGENT: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36
HTTP_UPGRADE_INSECURE_REQUESTS: 1
HTTP_CONNECTION: close
HTTP_X_FORWARDED_FOR: 80.7.192.7
HTTP_X_REAL_IP: 80.7.192.7
HTTP_HOST: 1099452403.1070340810.temp.prositehosting.co.uk
UNIQUE_ID: W@14@dHDBsa6gIedl5mtmwAAABY
on: 127.0.0.1
REDIRECT_STATUS: 200
REDIRECT_HANDLER: application/x-httpd-php72
REDIRECT_UNIQUE_ID: W@14@dHDBsa6gIedl5mtmwAAABY
REDIRECT_on: 127.0.0.1
FCGI_ROLE: RESPONDER
PHP_SELF: /modulizer/core/settings/diagnostics/index.php
REQUEST_TIME_FLOAT: 1542289657.6855
REQUEST_TIME: 1542289657

Thanks in advance