If you see the following errors or a white page when trying to charge a card that is returned as "Declined" from strip, this is due to the encoding of the strip lib files in nexus and a conflict with x-cache.
PHP Fatal error: Cannot access parent:: when current class scope has no parent
To resolve this issue, replace the encoded strip lib files with the non encoded versions.
Contact IPS Tech support for these files and link to this topic if needed.
Location of files
/admin/applications_addon/ips/nexus/sources/gateways/libs/
Source files are available here as well
https://github.com/stripe/stripe-php