dspMixFx for iPad

I have been using a UR44 and ipad air for almost 2 years in live/mobile situations as a mixer and recording interface. Great hardware. I don’t like ipad but it was the only way to get the dspmixfx software displayed large enough to use.

I run the dspmixfx and set volumes, eq, etc for any connected instruments and microphones.
Once set, I can leave the dspmixfx and run other ipad programs, pdf viewer, tuner etc. It all worked well.

Recently, if I leave the dspmixfx program and go another program or even the the desktop of the ipad, the audio cuts out. Audio returns after 5-10 seconds but many of the settings on the dspmixfx program have been dropped.

Thanks for any help available