Tempo randomly changes on playback

Since upgrading to Dorico 4 from 3.5, the same file plays back erratically.
Actually it just freezes when my metric modulations get complex - it stops playing. When resumed, the tempo jumps to a million miles per hour!
The same file worked fine in the prior version, but I can’t practice along with it any more.
Refer to section E on the attached.

Try this:

Change the tempo indication at bar 58 from x = 490 to e = 245, and the one at bar 63 from x = 572 to e = 286.
They are the same tempos, just expressed differently.

Thanks Steven, Yes I get that these are the same tempo “hacks” to achieve my modulations, just expressed at half the rate. This seems to have made Dorico 4 go ballistic, whilst version 3.5 was unfazed. This works now! Cheers!