[Plugin: Online Backup for WordPress] Backup Failed – Issue with 3rd Party Plugin?

I am attempting to back up my WordPress website at https://www.number4hair.com/. Each backup has failed and the activity log shows this as the last entry for each attempted date:

The backup failed: The server attempted to retrieve the data, but received junk from your blog. This can happen if your blog is not accessible over the internet. Otherwise, you may have a third-party plugin installed that is changing the backup data as the server tries to receive it. Please contact support if this is the case so we may improve compatibility.

I have the following 3rd party plugins activated on my site:
– Ambrosite Next/Previous Page Link Plus
– Contact Form 7
– Contact Form to DB Extension
– Convert Post Types
– EZPZ One Click Backup (I should probably deactive this one since it’s not working and I installed your plugin instead.)
– Google Analytics for WordPress
– Jigoshop
– Maintenance Mode
– Pie Register
– Related Posts Thumbnails
– Shadowbox JS
– Shadowbox JS – Use Title from Image
– SimpleMap
– Simplr User Registration Form
– TTFTitles
– WordPress Importer
– WP Export Users Plus

I have other plugins installed, but not activated. Any suggestions on what I can do to get my backups to work successfully?

Thanks!

https://www.ads-software.com/extend/plugins/wponlinebackup/