Hi Peter,
Hope your well
First of all I wouldn’t recommend touching the pins inside the USB2B plug
Both my SW EQ6-R mounts and SW EQ8-R mount have USB2B connections which are not solid connections ( you can wiggle the plug left and right 2mm ) and I’ve had no issues with drop outs during Mount operations for years.
USB2 is usually pretty stable up to 5m , however your PC / laptop may not be supplying enough USB power at various times to the mount.
Make sure you check USB Power Management ( attached )
As far as the cable being at fault , if you have replaced cables with different quality brands , I’m sure you’ve reduced the risk of the cable being at fault but in saying that I’d try a shorter 1m or 2m USB2B as well ( I only use Startech cables available through Mwave )
Also make sure the USB2B socket contacts on your mount are not corroded or tarnished due to moisture etc… contacts inside should be shiny tinned copper
The only other suggestion would be to monitor your USB traffic on your laptop to ensure it’s ok
https://support.microsoft.com/en-us/...6-2345d9c215ef
Hope others can pitch in and suggest other ideas
Hope you find the issue
All the best
Cheers
Martin