Ok... got a new internal batt sled for the 671 from marantz and it solved my power issues partially. Not loosing the ground anymore... but, now it turns off sometimes like the batts are dead, just after they are fully charged.
They are new batts as of a month ago and I've used them without any real problems with charging issues. Last night, fully charged, about 54 minutes into the show, the box shut off. Luckily I was checking levels JUST at that moment and was able to get it back up and running before missing too much.
Is there some sort of shim I need to do or something to modify this so that all the connections are working?
Thanks!