6300 transmit hum

Another possible source I described in another thread,
https://community.flexradio.com/flexradio/topics/6300-echo?topic-reply-list%5Bsettings%5D%5Bfilter_by%5D=all&topic-reply-list%5Bsettings%5D%5Breply_id%5D=15251211#reply_15251211

Jay - NO5J

I made several 40 SSB contacts today, some under strong, good S/N condx. Everyone said great audio, no echo or hum. Still, I have the echo and grrrrr in the monitor.

Thanks Tim.  Dudley sent me an expedited RMA number and shipping label yesterday.  I boxed my 6300 along with the Heil mic cable and ferrite beads (in case there's any question about the cable) and dropped it at the UPS store this morning.  Thanks for the great support.

One thing folks having audio issues might want to consider is building a terminator to act in place of the microphone. An open mic line could pick up random shack stuff (monitors, etc.) and provide a low-level of modulation. With a resistor (of mic impedance) using short leads in a shielded shell, you might see some improvement. At least for testing to rule out radio issues.