incompatibility with our social media poster plugin

Hello,
I try to figure out if the problem we have is related to FS-Poster plugin or to your Multi-Currency Plugin.

In most cases, when an automated posting is sent to any social media platform, the price in our base currency (CAD) is correctly shown on Facebook and other channels. But sometimes, maybe 1 of 7-10 postings, the price posted is in a different (wrong) currency. I can’t tell which one, but if the CAD price is, for example, 3.90 and the price shown within the Facebook post is 2.724586931, then I am sure this is the price in one of the other 3 currencies that we use in our online store (USD, GBP and EUR).

What is your opinion, and where could be the root of the problem?

Thank you.