The high beep tone is the Timecode message which is used to control the TRAKTOR Decks externally. This signal should not be audible while you are playing.
There are three possible reasons why you can hear the Timecode signal through the speakers:
Phono / Line Switch on DJ Mixer
The Phono / Line switch on your external DJ mixer is switched to Phono, so you hear the Timecode signal that comes out of your turntable instead of the audio signal from TRAKTOR that comes through the Master channel of your sound card. To hear the TRAKTOR output, simply switch the input on your external mixer from Phono to Line / CD.
Live Input Deck Flavor
You have set one or more Decks in TRAKTOR to Live Input Deck Flavor. In this mode TRAKTOR gives out the audio signal from the vinyl record running on the turntable. This allows you to switch from files played in TRAKTOR to actual vinyl records, as it often happens in a DJ-set situation. When the Live Input Deck Flavor is selected, the Deck is blank and no waveform is shown.
Direct Thru Mode
You have enabled Direct Thru mode. This mode is only available if you are using a TRAKTOR AUDIO 6 and TRAKTOR AUDIO 10 sound card with an external mixing setup. Direct Thru allows you to bypass the software when connecting external audio signals to the input channels of your sound card. The incoming audio signal is routed directly to the outputs of the same channel and remains unaffected by the TRAKTOR software. If you have enabled Direct Thru for the input channel of a timecode signal, the high beep audio of the Timecode medium will be routed to your external mixer.