Oanda being shady?????

I had long AUDUSD positions which I noticed was being charged interest. Lately I had long USDCAD which was charged interest.

I called them up and asked about it, and they stated they charge interest because of'speculation' of interest rate change by Oanda

So I asked them how soon do you actually do this before the news come out? And, when the interest rate decision does not go as plan, do we get refunded for all of the days that curiosity was charged?

The two callers that replied me dodge the questions fairly much. I was advised to email and they said they will'look to it' I am contemplating broker for the hiding behind the technique that was bush. If I decided to open a account, then cents interest could be hundreds of dollars in the long run. And why can you bill customers interest BEFORE the news???? I mean Oanda could rip off customers and earning fat profits out of that. And God knows they would do this prior to this interest rate report. Ridiculous

Can someone remark and hopefully bring to light?