MAC 10.9.5 & Firmware Issue

[Cspeegle]

I have a MAC running OS X 10.9.5 and tried to update the firmware using Insider 1.6.2 After 20 minutes the update hung and the progress bar showed no movement. I terminated the install and upgraded to 1.7.2. Now when I power on the amp all I have is a blinking Tap Delay button. I've tried all of the factory resets and tried to force the amp into update mode all to no avail. Any ideas on what else to try? I did purchase a two year warranty so I'm going to get an appointment tomorrow. However, I would love to not have to take it into the shop just to save the hassle.

[Cspeegle]

Update - I was able to upload the firmware. While trying various options from different posts I noticed that the Blackstar software had restarted and was attempting to load the firmware. I had tried unplugging the USB cable but this time I changed to a different cable and restarted the Insider software. It stared the download and completed it in about a minute. All functions seem to be working correctly. What a relief!!