A man died after being kept waiting in an ambulance outside Worcestershire Royal Hospital for an hour.
The BBC has been told staff had concerns about him so brought him in but as he entered the hospital he went into cardiac arrest on 27 November.
The hospital trust and West Midlands Ambulance Service said they were looking into what happened and offered their condolences to the family.
It added they were taking "positive action" to tackle waiting times.
In October, an ambulance crew waited more than 11 hours outside the same hospital with a patient.
On the same day, 34 ambulance patients waited more than an hour to be booked in at Worcester Royal.
Across 29 days in September, there were 257 one-hour delays at the site.
In the joint statement released on 3 December, the trust and ambulance service said there were "a number of ambulances waiting longer than we would want... despite the best efforts of staff."
"We are taking positive action to tackle this but we recognise there is more that we need to do," the spokesperson added.
They said the unit had "put in place procedures which are designed to support ambulance crews and protect patient safety if ambulances are waiting".
These measures include nurses carrying out regular checks on board to support crews and patients.
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