csnack, thanks for the suggestions. I am very hesitant about a full reboot of windows. This is a new machine (HP ElitePro 800 (I misstated earlier calling it a 4790 which is my printer). I am thinking towards a reinstall of Sonar. I had to install it fresh for the new machine. I will stay in touch.

Mark, thanks for the suggestion, did you mean just move the marker over one bar and start from there, if so, no change. As I said earlier to csnack I may just reinstall Sonar. 

You aren't using anything to start and stop the transport like a frontier designs tranzport are you. Used to have an issue like that when one of the midi ports for the control surface was set to the wrong place and was sending out notes to a midi device.

To add to the above, the OP never said exactly how you are starting/stopping the transport. As is sounds like the "ding" is the Windows error sound (not sure on this), it would be helpful to know if the transport is being started/stopped with a mouse on the transport controls, keyboard entry, or external device. When SONAR has focus, using a mouse or keyboard shortcut should not produce an error, but an external controller sending a signal into SONAR could, depending on how it is mapped. Even with SONAR in focus, the controller is what is relaying the message, and may be sending a message to something not online/recognized.

I am using a mouse to trigger the play button on the Sonar main screen. I do have a Zoom R-16 hooked up as a control surface but I haven't been using that lately. I have tried hitting the space bar and I still get the ding. I

OK. I looked into the zoom r-16 control surface to see if that was causing it. I reinstalled the r-16 driver and while in the midi-preferences section I checked all the boxes in the record section, assigned the midi sysx echo ports to all the available devices, record 64 buffers and playback 250 ms buffer. Also, in the project/ midi preferences I assigned the midi sync outputs to all available devices, enabled 'transmit  mtc time code' and enabled all available devices. Lo and behold the zoom r-16 started working as a control surface and THE DINGS WERE GONE!! Yahoo. Still I am not sure what stopped them. I am pretty sure it was a midi thing. I disconnected the zoom r-16 and the dings were still gone so I don't think that was any influence. Thanks for all your help and suggestions. Keep writing, playing and recording. Press on regardless. 

douglasc52
This may sound silly but, does anyone get a "ding " when they start and stop recording? I have turned off the metronome, tried to mute my midi notes and muted all my windows sounds still when I enable any track for recording audio, start recording and end recording I get this ding. It isn't recorded just monitored. Very annoying to me. I also get some strange low cord sounds when I add a track. Anybody hear this? I just got a new HP desktop and it is pretty powerful (Win10-64, I7-4790 with 16 G RAM) I am not having any trouble running Sonar but that ding is driving me crazy. Maybe I'm just obsessing but I don't recall that happening before. Any thoughts?

I had the exact problem and it was caused by conflicting MIDI ports. This had happened because Sonar had crashed and all of the ports became mangled, I had to reconfigure all of the MIDI ports and that exact sound was gone.

Always good to hear a problem solved brother. Now you know how to fix it if it happens again.