We've heard of frightening phone bills after overseas trips, but this is a big one.
Mobile service complaints and customer service complaints are both down more than a third compared with this time last year.
But the majority of complaints taken to the Telecommunications Industry Ombudsman (TIO) still concern mobile services - in particular, overseas roaming.
Roaming charges disputes are falling, but there are still some horrifying incidents.
In the year ending 30 September, the TIO received 235 complaints involving amounts over $5,000.
In one case, "a consumer who requested a $129 per month plan so she could make calls during a nine -week holiday in Europe, yet returned to a $75,000 bill. Subsequent bills increased the amount to $147,908, the highest disputed amount in the past 15 months".
Adoption of the TIO's recommendation that service providers should be able to restrict a consumer's access to roaming where charges are quickly accruing would help avoid the worst of these situations.
19% of complaints about overseas roaming charges during the last quarter were made by small businesses.
Despite incidents like the one above, the TIO reports complaints were down by more than 25% year-on-year, and a reduction was seen in every major category.
The areas that showed an increase in complaints included mobile coverage and credit default reports.
The TIO, along with at least one other ombudsman, has recommended that the minimum debt that can be reported to a credit agency should be increased from $100 to $300.
The adverse effects of such reports can be disproportionate for small debts, and some carriers are reporting unpaid bills that are in dispute.
There some signs that carriers may be resisting the TIO's resolution processes. Around 90% of complaints are settled almost immediately, and the rest are escalated through levels 2, 3 and 4 as necessary.
The number of complaints that reached level 3 last quarter rocketed up to 154, a 133% increase on the April-June figure.