I am attaching to this email an firmware upgrade. Please, upgrade your firmware and tested and let me know if this solves your problem.
To upgrade your waveform generator:
1. Click on the following link to download the latest firmware version available for the 4050 series:
2. Copy the file BK-V100R001B01D01P38R2.ADS to a USB drive and insert it into the waveform generator.
3. Turn on the waveform generator, and press the UTILITY button, and go to the second "page" and press "Update"
This will send you to the page where you save or recall states, waveform, etc.
4. Make sure you select the USB drive using the up and down arrows.
5. On the right menu, under "Browser" press once that button to change the selection to "File".
6. Using the knob or the arrows select the BK-V100R001B01D01P38R2.ADS file and press "Recall"
7. The unit will display a message saying to not turn off the generator and it will show you a message if the upgrade went well.
8. Reset the unit.
You now have a new firmware installed in your waveform generator.
Please test it and let us know if this firmware upgrade solved your problem.