Are you sure it is a v5? That would be closer to a v4. There are two ways to tell:
1 - There is a version # printed on the board
2 - Check the crystal filter crystal frequency stamped on the top of one of the 12 crystals that are all in a line. A v5 is 11.059, a v4 is 12.000
Another way is to check the audio circuit. The v4 uses discrete transistors, the v5 has an lm386 ic for audio output.
If a v5 OR v6 bfo were set to that frequency, it would be deaf.
The BFO needs to be set approximately 3.5 KHz below the crystal frequency, with final adjustments for each board.
Check the version number and then go to the BFO calibration page
Hope this helps,