We use the Browse API (https://api.ebay.com/buy/browse/v1/item_summary/search) endpoint and store the results for certain searches. A few months ago I noticed that occasionally the prices were being reported incorrectly, and finally realized it's because eBay seems to be randomly returning a different currency at times. Ex: We'll make a call to the eBay US marketplace where every previous call has returned all items in USD, but now suddenly in one call it's converted all items to GPB (or any other random currency) despite the fact that it's the exact same API call every time on our end.
From what I can tell it seems to be very intermittent and only happens in roughly 100 out of 1,000,000 API calls, but that's still a problem when it's reporting wildly incorrect prices due to some attempted currency conversion. We are sending the 'X-EBAY-C-MARKETPLACE-ID' header when making these calls, and can re-try the exact same call 10 seconds later with the correct results, so I don't understand what the issue is. Has anyone else experienced this issue and/or have any ideas on how to solve it?