I am getting distorted audio when I link to a REF reflector. The audio is almost unreadable. I re-flashed my SD card, reloaded the DStar Commander img file, and configured the DStar repeater and ircddb gateway. I am able to link and unlink to reflectors so I think the setup is correct. I do not have distorted audio using FM simplex or to local UHF/VHF repeaters. There are no local DStar repeaters near my QTH. My setup is as follows:
Kenwood TH-D74a with latest firmware DVMega Dual Band RasPi3 loaded with DStar Commander v2.01 Using 430.000 frequency to communicate with the DVMega
If, by distortion, you mean digital artifacting, which resembles the sound made by the R2D2 robot in the Star Wars movies, that is generally caused by loss or corruption of packets in the data stream coming to the Pi. In the case where the Pi is connected using a WiFi connection, interference from other wifi devices on that channel could be the cause. If using Wifi, try connecting the Pi using an ethernet cable and see if that improves things. If it does solve the problem, you can either leave it there, or you have some troubleshooting to do w/r/t wifi congestion. R2D2 can also be caused if your radio and your hotspot are just enough off-frequency from each other to cause intermittent packet loss. If you have a freq counter, then it's time to get the radio and the hotspot onto the bench. If not, you can experiment by moving the freq on either the radio or the hotspot up/down slightly (keeping notes) to see if there's an improvement when one is offset from the other.
Keep in mind, also, that 430.000 is in the ATV segment of the band plan, so if there's another ham very close by conducting ATV ops at high power near that freq, it could be a factor.
Bob (W6KD) Colorado Springs, CO D*STAR Hangouts: XRF555A (persistently linked to XRF002A) XRF720C (Colorado Front Range reflector)
Thank you for the quick response. I reset the DVMega, DStar Commander, and D74 frequency to 433 and all distortion went away. Audio is now clear. You were correct in that they must have been others using 430 and interfering. Thanks again for your help. 73 Howard/AD5IJ