Internal Error and logout when uploading pdf

Hi, this is a new install and whenever I attempt to upload a pdf (no matter the size) I get an Internal Error and am automatically logged out of Perch. Uploading other file types seems fine so presuming it's something to do with .pdf's. I'm contacting host as well but thought I'd see if this had been confronted before.

I've done a search of the forums and there seems to be a few situations similar but not quite the same as I've noticed that the pdf is actually uploaded to the server but not added to the resources table in the DB.

Any tips would be appreciated!

Perch information
Perch: 3.1.2
Production mode: Production (100)
Installed apps: content (3.1.2), assets (3.1.2), categories (3.1.2)
DB driver: PDO
DB tables: perch3_categories (0), perch3_category_counts (0), perch3_category_sets (0), perch3_content_index (0), perch3_content_items (1), perch3_content_regions (5), perch3_menu_items (8), perch3_navigation (0), perch3_navigation_pages (0), perch3_page_templates (0), perch3_pages (1), perch3_resource_log (0), perch3_resource_tags (0), perch3_resources (4), perch3_resources_to_tags (0), perch3_settings (21), perch3_user_passwords (0), perch3_user_privileges (27), perch3_user_role_privileges (2), perch3_user_roles (2), perch3_users (1)
Users: 1
App runtimes:
<?php
    $apps_list = [ 
    ];
Editor plug-ins:
H1: 51d65df97ec0ece80c5887dce8ac7139
L1: e4f3f3bbc55af5c4b9293594e5a7a979
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: 3.1.2
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
logoPath: /kontrol/resources/kontrol.jpg
PERCH_DEVELOPMENT: 10
PERCH_STAGING: 50
PERCH_PRODUCTION: 100
PERCH_DB_USERNAME: (redacted)_admin
PERCH_DB_SERVER: localhost
PERCH_DB_DATABASE: (redacted)_kontrol2
PERCH_DB_PREFIX: perch3_
PERCH_TZ: UTC
PERCH_EMAIL_FROM: simon@
PERCH_EMAIL_FROM_NAME: Simon
PERCH_LOGINPATH: /kontrol
PERCH_PATH: ..../public_html/kontrol
PERCH_CORE: ..../public_html/kontrol/core
PERCH_RESFILEPATH: ..../public_html/kontrol/resources
PERCH_RESPATH: ..../kontrol/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: ..../public_html/kontrol/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
Hosting settings
PHP: 5.6.37
Zend: 2.6.0
OS: Linux
SAPI: cgi-fcgi
Safe mode: not detected
MySQL client: mysqlnd 5.0.11-dev - 20120503 - $Id: 76b08b24596e12d4553bd41fc93cccd5bac2fe7a $
MySQL server: 5.5.5-10.1.35-MariaDB-cll-lve
Free disk space: 194.67 GB
Extensions: Core, date, ereg, libxml, openssl, pcre, zlib, filter, hash, pcntl, readline, Reflection, SPL, session, standard, cgi-fcgi, bcmath, ctype, curl, dom, mbstring, ftp, gd, iconv, intl, json, exif, mcrypt, mysqlnd, mysql, mysqli, PDO, pdo_mysql, pdo_sqlite, Phar, posix, pspell, SimpleXML, snmp, soap, sockets, sqlite3, tokenizer, xml, wddx, xmlreader, xmlrpc, xmlwriter, xsl, zip, imagick, mhash
GD: Yes
ImageMagick: Yes
PHP max upload size: 32M
PHP max form post size: 8M
PHP memory limit: 128M
Total max uploadable file size: 8M
Resource folder writeable: Yes
Session timeout: 24 minutes
Native JSON: Yes
Filter functions: Yes
Transliteration functions: Yes
CONTEXT_DOCUMENT_ROOT: ..../public_html
DOCUMENT_ROOT: ..../public_html
GATEWAY_INTERFACE: CGI/1.1
HTTP_ACCEPT: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8
HTTP_ACCEPT_ENCODING: gzip, deflate
HTTP_ACCEPT_LANGUAGE: en-US,en;q=0.9,vi;q=0.8
HTTP_CONNECTION: keep-alive
HTTP_COOKIE: cmsa=1; timezone=Australia/Sydney; PHPSESSID=ments75dh1052skj31bvpppg84
HTTP_DNT: 1
HTTP_HOST: .....com.au
HTTP_REFERER: ..../kontrol/core/settings/diagnostics/
HTTP_UPGRADE_INSECURE_REQUESTS: 1
HTTP_USER_AGENT: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36
PATH: /bin:/usr/bin
QUERY_STRING: extended
REDIRECT_STATUS: 200
REMOTE_ADDR: 110.142.45.132
REMOTE_PORT: 53863
REQUEST_METHOD: GET
REQUEST_SCHEME: http
REQUEST_URI: /kontrol/core/settings/diagnostics/?extended
SCRIPT_FILENAME:..../public_html/kontrol/core/settings/diagnostics/index.php
SCRIPT_NAME: /kontrol/core/settings/diagnostics/index.php
SCRIPT_URI: ..../kontrol/core/settings/diagnostics/
SCRIPT_URL: /kontrol/core/settings/diagnostics/
SERVER_ADDR: 122.201.80.194
SERVER_ADMIN: webmaster@....(redacted)
SERVER_NAME: ....(redacted)
SERVER_PORT: 80
SERVER_PROTOCOL: HTTP/1.1
SERVER_SOFTWARE: Apache
UNIQUE_ID: W6mpcN1tyMXBomMOJ2G2pAAAAEA
PHP_SELF: /kontrol/core/settings/diagnostics/index.php
REQUEST_TIME_FLOAT: 1537845616.43
REQUEST_TIME: 1537845616