freezing props

[Charlies lites]

I have an old f-48 v2.55 with 6 dumb receivers. I'm running an effect show, no audio. Each sequence is 4 minutes with each effect running either 10 seconds or 20 seconds, with 17 sequences. My problem is two props a cross with 62 pixels and a small matrix w/ 432 pixels on 3 ports. Both running off the same receiver. the matrix and the cross both freezes (stalls) at the same time, but not all the time.  the show ran for three days then froze. Today it froze 3 times. I do not know what sequence it stops on as I can only see these props when I go outside. Whit the sequence runs for some time before it happens could there be a receiver issue, or do I look at other issues?