After using Swift within the new 8.33 frequency areas there are a few bugs I have come across. If the frequency is .xx5 then Swift will tune the correct frequency for a split second then round the frequency down for example 121.805 springs back to 121.800 and 121.755 becomes 121.750. The usual .x25 and .x75 work as normal.
If the frequency is any .xx0 then this will work fine for example 135.580 and 121.890 will both work fine. This is tested on a multitude of aircraft including default, payware and freeware. Any work arounds to get Swift to stay on a .xx5 frequency when using the dot commands or right click on the ATC list functionality?
In FS9 using Swift 0.13.12, .xx5 frequencies round down to .xx0. The issue has been reported, and the developers are working on a fix. You can stay updated on the progress in the Swift Discord channel.