1994 Volvo 850 Transmission question

The transmission "sometimes" hesistates in shifting into first. This does
not occur in shifting into any other gear and it seems to happen more when
the car has warmed up. Again, this is very infrequent and random. We had
the transmission serviced about 2 weeks ago with the hope that this might
clear up any debris in the transmission, but it still does it. Has anyone
else had something similiar?

i have the same exact problem...it started out with hesitation in first gear and it happened for about one week and then just recently, while i came to a stop and then started to accelerate again, it hesistated a bit and started to accelerate at like 3 rpms...then the dreaded flashing arrow light came on...when i came to a stop again, my car wouldn't move no matter how much i pressed down on the accelerator. it was like my car was in neutral...i took it to my master mechanic and he thinks its an electrical problem because he disconnected the battery and connected it again and says that it drove again, but after a little while the dreaded flashing arrow light came on...they couldnt find the sensor in the engine so they assume its in the transmission sensor. so far i havent heard from my mechanic so i'll keep it updated. the mechanic says the car drove nicely, but i'm getting skeptical about the tranny, i can't afford a new one. i hear about similar problems where they fix the senors in the tranny but then the tranny breaks down a few months later