Pronunciation of Dusun

Research continues at UBD on the pronunciation of Dusun. The following website highlights recent efforts:

http://fass.ubd.edu.bn/research/dusun/index.html

One goal of this work is to enable readers to listen to the material as they read about it. Here is the opening phrase of the 'North Wind and the Sun' passage.

As you can hear, one key feature of Dusun is the pronunciation of 'r' as [ɣ], a voiced velar fricative; so utara' ('north') is [utaɣaʔ].

My dream is that , one day, all academic papers on pronunciation will have embedded sounds, so you can always listed to the material as you read the paper.

Pronunciation of 'Sultan'

How should I pronounce 'Sultan'? Should it be [sʊltən] (the first syllable rhyming with 'full')? Or should it be [sʌltən] (the first syllable rhyming with 'gull')?

This morning, I asked this question to a room full of people, mostly Bruneians, and the consensus was for [sʊltən]; but Wells's Longman Pronunciation Dictionary (2008, p. 791) only gives [sʌltən]:

So, is John Wells wrong?

Perhaps it should be [sʊltən] in Brunei and Malaysia but [sʌltən] in the UK, the USA and elsewhere?

Actually, on reflection, in the context of Brunei and Malaysia, it should probably be [sʊltæn], with a full vowel in the second syllable. I must remember to use that form in the future.