Would you be willing to try disabling any auto-sleep settings? If it makes no difference then you could turn them back on, so no loss.
The laptop is an i7 quadcore/16GB RAM desktop replacement job - and it stays plugged in. I just checked and the power scheme is "sleep -> never" when plugged in. As I recall, I used this same machine a lot for a month or two a couple of years back and on an off since with RM 2.x and never had any issues.