Using the latest master on testnet, after leaving the wallet running/staking for some time, then when PC goes to sleep, after booting it again this is the output in terminal:
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EXCEPTION: N5boost10wrapexceptINS_15condition_errorEEE
boost::condition_variable::do_wait_until failed in pthread_cond_timedwait: Invalid argument
pivx in scheduler
terminate called after throwing an instance of 'boost::wrapexcept<boost::condition_error>'
what(): boost::condition_variable::do_wait_until failed in pthread_cond_timedwait: Invalid argument
Aborted (core dumped)
OS: Ubuntu Linux 20.04