Are inputs and outputs translated before and/or after going through the main GPT model?

I’ve noticed a recurring question pop up among our clients: Does GPT resort to translations when dealing with languages other than English? This is spurred by the perception that GPT carries an ‘American’ flavor in its responses, leading some to speculate that translation must be at work somewhere in its process.

I always tell them that GPT is a multiligual model that is mostly trained on English/American texts hence the bias towards the American tone of voice. However some other person (on the internet), who claims to be into AI, says that he knows that GPT uses translation.

So, I would like to know if a single GPT model answers questions regardless of the language used, or is there some logic behind the scenes that routes the text through another system when it detects a language other than English?