Don’t remember. :-) But if faced with it now the first thing I’d try would be to increase (slightly) the VTF and see if that solved the problem. VTF is a moving target but your cartridge maker should have spec’d a range. The other possibility (if not probability) is that you have the anti-skate set slightly off and it is presently walking off the light grove at the beginning of the record until it gets into the deeper groove where the music resides and the physical nature of the groove arrests its movement. If you can correct the problem with adjustments of both, I’d select the antiskate adjustment - likely to cause the least amount of change to the signal. Have fun.................!
BTW I just read larryi's suggestion - he could be right - simple to rule out.