504 Gateway Time-out nginx intermittent problems

I am developing a cs-cart site for the first time. I’ve made no modifications to the core, and have only entered a few products for testing purposes. I’ve made some template changes and installed a couple of add-ons.

Starting about a month ago, I began getting 504 gateway time-out errors. Once I got one, the errors would continue for some time. The site is on a robust, dedicated server that is running several other websites without issue. Everything is working great on this server.

I’ve had tech support look at this issue a few times. Once, the issue cleared up when they repaired all the database tables.

I obviously can’t launch this site if the problem continues, so I’m wondering if anyone has seen this issue and whether they have ideas about how to troubleshoot. By the way, someone may suggest that I try a different host. I’m with Knownhost and have hosted over 100 sites with them on their VPS and dedicated server platforms. I’m very happy with them and I’m sure they can make any adjustments I need. thanks for any suggestions!

I can’t access my site to check at the moment, but I believe I’m using version 3.0.6.