One might consider for a moment how it came about. First, there are no final consonant clusters in Malay; so when a word such as bank gets borrowed into Malay, it is usually pronounced as [baŋ], with no final [k]. And it is easy to see how confusion between thang instead of thank could occur.
Next, there were originally no labiodental fricatives /f, v/ in Malay, though they do occur in some borrowed words, such as faham ('understand'), fikir ('think') and fitnah ('slander') from Arabic, and fail ('file'), fius ('fuse') and filem ('film') from English. Initial /v/ is less common than initial /f/, but we do find visa and van from English.
My dictionary lists 85 words with initial /f/ and only 34 with initial /v/, so it seems /f/ is rather more common. Furthermore, all the words with initial /v/ are from English, while many of those with /f/ are from Arabic, so the latter probably feels a bit more comfortable as a sound in Malay.
And this might explain the mistake at the start of fisiting.
